|This article is about the special. You may be looking for the book.|
- “But I wasn't quick enough to save the treasure, Sir".
"Please don't worry about the treasure, Thomas. My engines are much more important to me than any treasure. And you, Thomas, are my number one.”
- ―Thomas and Sir Topham Hatt
Sodor's Legend of the Lost Treasure is the second 2015 Thomas & Friends special.
It is a bright sunny day on Sodor, as Thomas chuffs along his branch line with Annie and Clarabel. When he sees Bertie, he decides to have a race with him, but nearly gets into trouble along the way, narrowly avoiding rail work and nearly having a head-on collision with Toby when he passes a red signal. Bertie believes that he will win, due to him being in first place for the majority of the race, but his chances of winning become slim when he has to slow down for Oliver the excavator, who is slowly trundling along the small countryside road. Thomas gets the upper hand in the race and Bertie finally gets past Oliver, who takes a shortcut, passing by a familiar man on a bicycle. When Thomas stops at Ffarquhar, he is very pleased with himself for winning, but Annie and Clarabel are not pleased and sternly scold him for racing, but he just ignores their scolding, remarking he has raced on his branch line for years. Bertie arrives at the station, cross that he has lost, remarking that ever since the new branch line's construction site, he has been held-up by construction vehicles. Annie and Clarabel fear their branch line will be closed in favour of the new one, but Thomas dismisses it.
Meanwhile, Marion is on her way to the construction yard, fascinated by the enchanted scenery of the forest at Arlesburgh. As she chuffs along, two small engines dart pass her, taking her by surprise. She shuts her eyes and bumps into Toad and Oliver, who are waiting at the ballast chute. A small red engine races up the chute with some hoppers, frightening Marion. Toad introduces Marion to Rex, Mike and Bert, three miniature engines. Marion is interested by the little engines' size, asking if they are real. A cross Mike tells her they are real and that they deliver ballast, wool and passengers for the big railway. Toad and Oliver then leave for the construction yard, just as two black engines race past Marion.
At the construction yard, Duck is shunting trucks, just as Donald and Douglas arrive. Duck is delighted to see them, remarking that it has been ages since he has last seen them, but the twins tell him they have only been away to fetch new rails and sleepers for the construction. Meanwhile, Jack and Alfie are getting to work, just as Oliver arrives, apologising for being late as he took a wrong turn.
The next morning, Thomas cannot wake up. His fire goes out and there is not enough steam to get him going. The other engines all wake him up, reminding him that he needs to shunt Gordon's coaches, but Thomas is in no hurry to do that. Meanwhile, Gordon grumpily waits at Knapford for Thomas, just as he finally arrives. Annie and Clarabel remind Thomas it is time for their first train, but Thomas tells them he has to get Gordon's coaches first, criticising Gordon for being lazy for not getting his own coaches. Gordon tells Thomas that he knows full well that tender engines are too large for shunting, telling him that is what common little tank engines do. Determined to prove Gordon wrong, Thomas decides that he will pull the express today and thunders out of the station with the coaches. Unfortunately, due to being behind the coaches, this results in an accident occurring when he fails to slow down, collides with Emily as she tried to stop to avoid being hit, and leading to the express coaches coming off the rails.
Meanwhile, at the construction site, Marion tries to play 'Guess What's in My Shovel' with Donald, but he does not have time to play. She then turns her attention to Oliver the excavator, but he tells her that all he has in his bucket is dirt and rocks. When she asks what his name is, Marion is surprised to find out that the excavator's name is Oliver, believing that he turned himself from a railway engine into a digger. Oliver tries to explain the situation to her, but his attempts to do so are futile, as she believes the Arlesdale engines really are magic and granted him a wish, deciding that she will make a wish as well.
Back at Knapford, the Fat Controller has arrived to inspect the damage. Thomas tries to pin the blame on Gordon, Toby and Emily, but the Fat Controller does not believe him. He tells Thomas that he will be sending him to the construction yard as punishment. When Thomas asks who will look after his branch line, a new purple tank engine called Ryan shows up. The Fat Controller welcomes Ryan to his railway, while Thomas looks on, shocked.
At the construction site, work goes on as usual. However, trouble arises when the ground beneath the tracks begins to crumble and the workmen flag down Donald just before he can pass over the line. Some engineers are called and after inspecting the area of bad track, they deem it unsafe, forcing the workmen to re-route the line.
Meanwhile at Arlesburgh Junction the small engines are delivering ballast for the new branch line, when Thomas sadly puffs in. When asked what is wrong by Bert, Thomas crossly tells them about Ryan replacing him and what Gordon told him. The small engines tell him that bigger engines always act superior than smaller engines, even if they come out on top. The small engines then burst into song to cheer Thomas up, but unknowingly make him overconfident. When Thomas arrives at the construction yard, he remembers what the small engines told him about rails and sleepers coming before ballast and eagerly shunts some flatbeds of sleepers and rails along to the construction site. The workmen try to stop him from travelling along the unstable track, but Thomas thinks they are cheering for him. He bursts through the safety barriers and rolls over the unstable ground, just as it gives way and a large sinkhole forms. Thomas tries to escape the hole, but the trucks pull him in as his crew jumps clear. Thomas is badly damaged by the fall, but sees an abandoned pirate ship in the cavern.
At Knapford, Ryan arrives in the yard, introducing himself to Annie and Clarabel, who wonder where Thomas is. Meanwhile, at the cavern, Thomas is lifted out by Rocky, the Fat Controller reprimanding him for ignoring the danger signs. Thomas tries to tell the Fat Controller he was not responsible for the accident and tries to tell him about the pirate ship, but the Fat Controller is not interested in his excuses, telling Emily to send him to the Steamworks. As this goes on, an elderly man watches Thomas being recovered from the cavern with his telescope, stomping on his sailboat for bobbing about in the water.
Thomas is sent to the Steamworks, but is in no hurry to get back to work, telling Victor and Kevin that the Fat Controller has already replaced him. However, Victor reassures Thomas that the Fat Controller would never replace him and that he wants him to get back to work as soon as he can, while Kevin tells Thomas that despite all his accidents, he still works at the Steamworks. Just then, Edward arrives and tells them that Rocky has discovered the pirate ship, much to Thomas' fury. At the sinkhole, Rocky lifts the pirate ship out, much to everyone's amazement. Jack believes that the ship was put into the cavern by being folded up like a ship in a bottle, but Donald and Douglas dismiss Jack's theory, believing that the cavern must once have been open to the sea and the ship must sailed in then. Marion believes that if there is a pirate ship around, then there must be buried treasure. This gives her an idea for a wish and she sets off to Arlesburgh Junction at once.
At the junction, the small engines are still at work, just as they hear Marion coming. Both Rex and Bert immediately flee, leaving Mike behind. Before he can get off of the chute, however, Marion stops him and begins telling him her wish. Mike immediately breaks free and escapes, but this only fuels Marion's belief that the small engines are magical. Meanwhile, Donald and Douglas deliver the pirate ship to Arlesburgh Harbour, the same man and sailboat from earlier watching them.
That night, Henry is pulling the Flying Kipper, when he suddenly sees a white sailboat gliding down the rails. Surprised, he runs down a siding and hits the buffers, but when he looks back, the boat has gone. The next morning, he tries to tell the other engines at Brendam Docks, but most of them think he was just seeing things. Salty then shows up and tells the engines the legend of the Lost Pirate, Captain Calles, who was a feared pirate who stole much treasure from merchant ships. However, his activities gained attention from the Navy, who hunted him down. To escape from them, Calles sailed his ship into a cavern and buried his treasure nearby. However, his map revealing the location of the treasure was lost and he never found either the map or the treasure again. Salty says that the Lost Pirate is still out there on his ghostly ship, trying to find his treasure, but Cranky scoffs at the idea of a ghost pirate. The other engines all leave, with Henry still protesting that he saw the ghost. Meanwhile, Thomas passes through Arlesburgh when he sees the pirate ship, angrily saying that he was the one who found the ship, not Rocky. While he is not looking, the man from earlier climbs onto the ship and looks around.
Thomas arrives back at the construction yard and fills up on coal, surprised to find Ryan there. He asks the Fat Controller if he can now go back to his branch line, but the Fat Controller tells him that Percy is already doing his work and tells Thomas to collect some more ballast, leaving Thomas to lament at the fact he is no longer the Fat Controller's No. 1 engine. Meanwhile, Marion is helping Oliver and Alfie dig at a cliffside, telling them about how she made a wish to Mike.
When Thomas arrives at Arlesburgh Junction, he is blowing sparks and black smoke from his funnel. The small engines conclude that he must have had some bad coal. That night, he takes on some fresh coal and heads to the sheds, but finds Ryan already there. Ryan tries to coax Thomas into the shed, but Thomas chooses to sleep on a siding by himself, upsetting Ryan. As he sleeps on a siding, he suddenly wakes up to see a sailboat sailing along down the line, so he decides to follow after it. Thomas stops at the sinkhole to find the sailboat and its owner there, accidentally getting their attention. The man turns his attention to Thomas and asks him who he is, to which Thomas introduces himself and mentions how he found the pirate ship, but Rocky stole the credit from him. The man introduces himself as Sailor John, while his sailboat also introduces himself as Skiff, telling Thomas that they are looking for treasure. Sailor John asks Thomas if he would like to help him find the treasure, to which he agrees to. Tying a harness around his waist and to Thomas' buffer, Sailor John lowers himself into the cavern. Skiff tells Thomas that they have been sailing around the coast for years to find the treasure, as well as telling Thomas about how Sailor John gave him rail wheels to search for the treasure on land. Sailor John finds Calles' map inside of the cavern and is pulled back out by Thomas. Skiff reminds Sailor John that the sun is rising and John tells Thomas that he and Skiff have to go back home, telling him they forgot their shovels. Since Skiff cannot move due to there being no winds, Thomas pushes him along back to the harbour, where he sails off with Sailor John back home.
Later that morning, Thomas returns back to the construction yard, just as Ryan begins questioning him on his whereabouts the previous night. Thomas tells Ryan that he must have been having a dream and then questions him when he begins to fill up with coal. Thomas knows fully well that the coal in that hopper is bad, but does not say anything to Ryan about it. Meanwhile, Marion tries to work on the next cutting, but the rock is too hard. When told that they have to wait for a train of dynamite from Brendam Docks, Marion suggests to Oliver that he should make a wish and turn back into an engine, but Oliver, going along with what Marion says, tells her that may not work. When Ryan returns, he is emitting black smoke and sparks from his funnel. Just as he begins to puff away, sparks from his funnel set the dynamite in one of his trucks alight, leading him to panic. This causes him, Jack, Alfie and Marion to pass around a crate of dynamite with a lit stick, until it lands back into the trucks. Quickly thinking, Thomas buffers up to the trucks and shunts them into the cavern, causing the dynamite to explode. He is congratulated by the others, but the Fat Controller is furious, due to the scenario looking like Thomas was messing about with the dynamite and, fed up with Thomas having caused so much confusion and delay, sends him to his shed for the rest of the afternoon, along with ordering everybody else to go back to work. The diggers attempt to continue work on the cutting, but without dynamite, work is slow. Marion finds a chest in the cliffside and tries to tell Alfie and Oliver, but by then, they have already left.
That night, Thomas rests on a siding, just as he sees Skiff and Sailor John heading back to the sinkhole. He follows after them and agrees to help them try to find the treasure. But no matter where they look, they cannot seem to find them. Sailor John immediately accuses Thomas of finding the treasure first, citing that only they and Skiff have seen the map and he has been with Skiff night and day. Skiff reminds Sailor John the sun is rising and Sailor John leaves as Marion wakes up. Upset, Thomas puffs away, but Marion bumps into him, causing her to dump the chest on him, revealing its contents - the treasure! The Fat Controller is delighted with Marion's discovery and plans to display the treasure in the museum, while he sends Thomas to the waste dump to deliver some construction waste.
As Thomas puffs along the cliffs, Henry thunders past, frightened by the Lost Pirate. As he rounds the bend, Thomas finds that the Lost Pirate is actually Sailor John and Skiff. Sailor John demands to know where the treasure is. Thomas tells him that the Fat Controller has it and plans to give it to the museum, infuriating Sailor John, despite his previous claims to Skiff that the treasure would go there. Sailor John angrily proclaims that he will get the treasure back, but Thomas stands up to him, telling him that the treasure doesn't belong to him then shoving him and Skiff aside, leaving John to pout.
Thomas returns to Knapford, where he overhears the Fat Controller speaking on the phone about the treasure. The Fat Controller says that the treasure will be stored at Knapford overnight, worrying Thomas. He returns to the construction yard, where he meets Ryan again. The two make amends for what happened earlier and Ryan once again tries to offer Thomas a space in the shed, but Thomas tells him he plans to stay at Knapford.
That night, Thomas sleeps on a siding outside of the station, waiting for Sailor John and Skiff to show up. Hours later, as he is asleep, Skiff and Sailor John arrive. Skiff asks what they are doing, but Sailor John does not tell him. John then jumps off of Skiff, hides from a passing Henry and then blows up the Fat Controller's safe with a stick of dynamite and steals the treasure. Skiff wants to have no part in his scheme, but has no choice but to follow along. The explosion and Sailor John stomping on Skiff wakes Thomas up, who begins pursuing him, albeit having troubles steaming up.
At Tidmouth Sheds, Henry races past, frightened by Skiff and Sailor John, who follow along shortly afterwards. Annie and Clarabel believe they are having a strange dream, until Thomas thunders past, chasing after Sailor John and Skiff. In order to keep up with them, Thomas has to race through a red signal, almost colliding with Gordon and a late-night express. Thomas heads through a tunnel and up a hill, where he finds the pirate ship there and tied to Skiff. Sailor John picks up the anchor and lets the ship roll down the hill. Meanwhile at Arlesburgh Junction, Ryan's worry about why Thomas stayed at Knapford prevents him from sleeping and he panics when he sees the ship approaching. Thomas passes by and tells the small engines to stop the ship. Though Sailor John scoffs at the engines' miniature size, the three small engines bravely push some ballast hoppers off of the chute and onto the standard gauge line. Most of the hoppers are shoved aside, but one gets stuck under the flatbed and causes the pirate ship to lose momentum. A rope then gets fastened to Ryan's buffer and the tank engine suddenly brakes, hitting a buffer stop and causing the ship to topple over. Thomas congratulates Ryan and puffs on.
As the morning sun rises, the chase is still going on. Thomas tries to tell Skiff to stop, but he cannot. Sailor John tries to stop Thomas, attempting to throw an anchor and shovel at him. He then tries to destroy Thomas by blowing him up with dynamite, but Skiff tips over slightly, causing John to lose his aim. Skiff encourages Thomas to derail him, just as John violently hits Thomas in the face with the oar, threatening to have Skiff in the dry dock sail-less. Thomas furiously bumps into Skiff, but accidentally sends him down a different line, much to Sailor John's delight. Though it seems as if there is no hope left, Thomas suddenly notices that his line crosses over Skiff's, immediately picking up speed and ramming into him. Skiff is re-railed onto Thomas' line, but their relief is short-lived, just as Thomas notices the line runs into the sea. Thomas falls into the sea and rests atop of Skiff's chassis, while Skiff and Sailor John sail away. Skiff tries to tell Sailor John to go back and help Thomas, but John threatens to destroy him if he tries to betray him. Suddenly, a wave pushes them along and causes them to lose the oar. Sailor John orders Skiff to stop it, telling him he is letting in water, but Skiff tells him that the treasure is too heavy and is making him sink, telling John to throw it overboard. Sailor John does not want to and forces Skiff to sail on, just as a huge wave forms. Skiff is capsized by the oncoming wave and the treasure chest sinks to the bottom of the sea. Thomas watches on from the harbour, thinking this is the end of Skiff, just as Skiff turns back over.
Later that morning, the police catch Sailor John and arrest him. Thomas is lifted onto a flatbed by Rocky and upon seeing the Fat Controller, he tries to apologise, thinking that he would be cross with him, especially after Thomas' previous mishaps. However, the Fat Controller tells Thomas that he is proud of him for trying to stop Sailor John and that Ryan told him everything. Thomas is still upset that the treasure is lost, but the Fat Controller is not concerned about that, telling Thomas that he's just happy he is alright and that his engines are more important to him than any old treasure and that Thomas is his No. 1. Thomas smiles and his number is shown to be back.
At last, the construction of the new branch line running to Harwick is now complete. Marion finds out that there are, indeed, two Olivers on Sodor and Thomas, fully repaired, arrives with Annie and Clarabel for the opening ceremony. The Fat Controller announces that Ryan will be handling the goods traffic, while an old friend looks after the passengers. Thomas says he already has a branch line, but the old friend is revealed to actually be Daisy. The branch line is declared open and Thomas and the other engines steam along down the new line, meeting up with Skiff again, who is now carrying railboat tours. Divers recover the treasure and that night, Thomas and Skiff watch from the harbour as fireworks go off.
- Donald and Douglas
- Bill and Ben
- Annie and Clarabel
- Sir Topham Hatt
- Sodor Brass Band Leader
- The Ffarquhar Policeman
- The Blond Haired Girl
- Some Workmen
- Rocky (does not speak)
- The Engineers (does not speak)
- Rosie (cameo)
- Stanley (cameo)
- Porter (cameo)
- Samson (cameo)
- Diesel (cameo)
- Mavis (cameo)
- Henrietta (cameo)
- Max and Monty (cameo)
- Captain (cameo)
- Lady Hatt (cameo)
- Bridget Hatt (cameo)
- Stephen Hatt (cameo)
- Sir Robert Norramby (cameo)
- Farmer Trotter (cameo)
- Dowager Hatt (cameo)
- Sodor Brass Band (cameo)
- The Ginger-haired Boy (cameo)
- The Bird Watcher (cameo)
- The Teacher (cameo)
- The Lady with the Big Hat (cameo)
- The Great Railway Show Judge (cameo)
- The Man with the Green Waistcoat and Grey Hair (cameo)
- The Ffarquhar Stationmaster (cameo)
- Big Mickey (faceless, cameo)
- Sailor John
- The Divers
- Captain Calles (does not speak)
- The Thin Clergyman (cameo)
- Thomas' Branch Line
- Tower Windmill
- Road and Rail Runby and Road Bridge
- The Little Western
- Harwick Branch Line
- Arlesburgh Junction
- Arlesburgh Works
- Arlesburgh Goods Yard
- The Construction Yard
- Tidmouth Sheds
- Sir Topham Hatt's Office
- MC BUNN
- Knapford Station Yard
- Arlesburgh Harbour
- Calles Cavern
- Sodor Steamworks
- Brendam Docks
- Sodor Shipping Company
- Coastal Cliffs
- Conrad's Bridge
- Mavis' Shed
- Anopha Quarry
- The Works
- Black Loch (portrait)
- Harwick (mentioned)
- Arlesburgh Maritime Museum (mentioned)
- Whiff's Waste Dump (mentioned)
- Dryaw (name on signpost)
- Elsbridge (name on signpost)
- Hackenbeck (name on signpost)
- Ulfstead Castle (map only)
- Peel Godred (map only)
- Loey Machan (map only)
- The Mainland (map only)
- Isle of Man (map only)
- Post Windmill (dropped)
UK, AUS and NZ
- John Hasler as Thomas
- Keith Wickham as Edward, Henry, Gordon, James, Percy, Salty, Bert, Bertie, the Fat Controller, Some Workmen, the Sodor Brass Band Leader, Thomas' Fireman, the Policeman and the Divers
- Rob Rackstraw as Toby
- Steven Kynman as Duck and Jack
- Joe Mills as Donald, Douglas, Oliver and Toad
- Teresa Gallagher as Emily, Daisy, Annie, Clarabel and Some Children
- Olivia Colman as Marion
- Matt Wilkinson as Cranky and Kevin
- Tom Stourton as Rex
- Tim Whitnall as Mike and Oliver the Excavator
- Jonathan Broadbent as Bill and Ben
- David Bedella as Victor
- Eddie Redmayne as Ryan
- Jamie Campbell Bower as Skiff
- John Hurt as Sailor John
- Nathan Clarke as Alfie
USA and CAN
- Joseph May as Thomas
- William Hope as Edward and Toby
- Kerry Shale as Henry, Gordon and Kevin
- Rob Rackstraw as James
- Christopher Ragland as Percy
- Steven Kynman as Duck
- Joe Mills as Donald, Douglas, Oliver and Toad
- Jules de Jongh as Emily
- Keith Wickham as Salty, Bert, Bertie, Sir Topham Hatt, Some Workmen, the Sodor Brass Band Leader, Thomas' Fireman, the Policeman and the Diver
- David Bedella as Victor
- Olivia Colman as Marion
- Teresa Gallagher as Daisy, Annie, Clarabel and Some Children
- David Menkin as Jack
- Tom Stourton as Rex
- Glenn Wrage as Cranky
- Tim Whitnall as Mike and Oliver the Excavator
- Jonathan Broadbent as Bill and Ben
- Eddie Redmayne as Ryan
- Jamie Campbell Bower as Skiff
- John Hurt as Sailor John
- Nathan Clarke as Alfie
- We Make a Team Together music video
- Never Overlook a Little Engine music video
- Guess Who? puzzles - Ryan, Bert, Rex and Mike, Skiff, Donald and Douglas
"Sodor's Legend of the Lost Treasure" was met with mostly positive reviews from critics who praised the direction and solid plot through critical of the films' somewhat dark undertones.
Andrew Pulver of The Guardian gave the film a 3/5 stating, "Like Tale of the Brave, Lost Treasure jams locomotive action together with a pop motif supposedly beloved of kids: Brave had dinosaurs, Treasure has pirates."
- The special grossed £620,106 ($810,735.27 in American money) at the UK box office.
- Before development for this special was worked on, another special was being developed. However, due to not reaching Mattel's greenlight, the idea was dropped.
- On the day of the special's UK theatrical release, Sir John Hurt was knighted for his services to drama by Queen Elizabeth II at Windsor Castle.
- This special won Evcom Screen Awards Gold Award for Music.
- The special aired on Virgin Atlantic flights out of London from 1st - 8th August.
- This special takes place between the nineteenth and twentieth series. However, there are some hints with voice actors and changes that this was produced before the nineteenth series in 2014, these being:
- Stanley not having a lamp, lamp-iron, brake-pipe or brake-pipe outlets all of which he received in the nineteenth series.
- Keith Wickham voiced Percy in the UK dub.
- Tidmouth Sheds still lacking the buffers that appeared behind each berth partway through the nineteenth series.
- Jennifer Hill still producing for Arc before leaving July 2015, whilst the last five episodes of the nineteenth series, the next special and the first seven episodes of the twentieth series were produced by Robert Anderson.
- From this special until Big World! Big Adventures!, every new special is produced before the series that takes place before it. Because of this, it results in several continuity errors that are the result of animation, voice acting or staff members.
- This special marks the first of multiple things:
- The first appearances of the Arlesdale Railway and the Thin Clergyman in the television series. The Awdry family was consulted for rendering the latter for the special.
- The first time since the fourth series episode, Paint Pots and Queens in which a real person appears, as well as the first production since that series to introduce a railway and engines from The Railway Series.
- Donald, Douglas, Daisy, Alfie, Oliver the Excavator, Max and Monty's first appearances in full CGI; this also marks the first of a few things for these characters:
- Donald and Douglas:
- Oliver the Excavator:
- His first appearance since The Great Discovery.
- Max and Monty:
- Their first appearance since the twelfth series episode, Percy and the Bandstand.
- The first appearance of Arlesburgh Harbour since the third series episode, Thomas and Percy's Christmas Adventure.
- The first time Harwick is mentioned in the television series.
- The first full-length CGI special not to feature a stylised opening sequence, excluding The Adventure Begins.
- The first special in which engines sing an original song.
- The first time in the television series that The Mainland is explicitly shown to be England.
- The first time all engines numbered 1 to 11 have appeared and spoken in full CGI. This does not happen again until Big World! Big Adventures.
- The first time The Pack is seen interacting with engines other than Thomas and Percy, with those characters being Duck, Oliver, Donald, Douglas, Toad, and Marion While being the first time they interact with characters as such as Marion and Toad who are characters not numbered 1-11.
- The first special where Rob Rackstraw voices Toby in the UK and Christopher Ragland voices Percy in the US.
- Toby, Diesel, Victor, Jack and Captain's first appearances in a special since King of the Railway.
- The first time characters who have the same name appear at the same time.
- Duck, Oliver and Daisy's first speaking roles in a special.
- Donald, Douglas, Samson and Toad's first appearances in a special, not counting Toad's appearance as a scrap model in Thomas and the Magic Railroad, his other faceless special appearance, and a cameo in Tale of the Brave's trailer.
- Nathan Clarke and Jamie Campbell Bower join the voice cast and Eddie Redmayne and John Hurt make special guest voice appearances.
- This special marks the one-time of a few things:
- The only production to feature Eddie Redmayne as part of the voice cast to date. As a result, Steven Kynman took over Redmayne's role of Ryan from the twentieth series onwards. It is also the only production to feature John Hurt as part of the voice cast prior to his death.
- The first and only appearance of Sailor John until Big World! Big Adventures! and his only speaking role to date.
- The first and only special to date in which Percy only has one line, being "Wake up, lazybones!" He is also one of the few characters in the special to have one line, with the others being Emily who exclaims "Thomas!" when he is shunting Gordon's express coaches through the junction, Bill and Ben during the scene at Brendam Docks and Daisy towards the end.
- The first and only special narrated by Ane Barmen in Norway.
- Drafts of the film's script were shown in the YouTube video, 70 Years of Friendship. According to these drafts:
- "The Great Treasure Hunt" and "Legend of the Lost Treasure" were both working titles for this special.
- The special was to open with Thomas passing the original windmill. The final film instead uses stock footage of Thomas passing the Tower Windmill from the nineteenth series episode, Thomas the Babysitter, possibly due to time constraints.
- A rendition of the original opening theme was considered for the special. However, this idea ultimately did not materialise in the final film.
- Thomas' coaches remind him that the passengers do not like being bounced like peas in a pod, as Andrew Brenner had misquoted the line during an interview with SiF. The line is correctly quoted ("...bounced about like peas in a frying pan") in the final special.
- This special marks the last of a few things:
- Jennifer Hill's last special as producer.
- Edward Catchpole and Stephen Gallop's last special as executive producers.
- The last time where Keith Wickham voices Percy in the UK. Nigel Pilkington would later take over the role in the nineteenth series.
- The last special to be composed by Robert and Peter Hartshorne. Chris Renshaw took over as composer of the series starting with The Great Race.
- So far, the last special to date in which the narrator reads out the title.
- The last special until Steam Team to the Rescue in which Thomas does not leave Sodor.
- The last special to date in which Marion is voiced by Olivia Colman. From The Great Race onwards, Teresa Gallagher provides her voice via singing appearances.
- The last special dubbed in Norwegian until Big World! Big Adventures!
- A still from the eighth series episode, Emily's New Route appears in the Fat Controller's office.
- Some parts of the special were cut out of the PBS broadcast due to time constraints:
- The engines trying to wake up Thomas.
- Marion talking to Alfie and Oliver while they were digging.
- A few scenes of the engines on the new branch line was cut along with the song.
- On the week of its DVD release in the UK, Ben Dowell gave the special a four-star rating and branded it as the DVD of the week in the Radio Times.
- A few references were made throughout the special:
- The opening pays homage to the original television series opening, with Thomas passing a windmill, going under a bridge and eventually pulling into Ffarquhar station.
- Clarabel tells Thomas that his passengers do not like being bounced like peas in a frying pan. This is a reference to the first series episode, Thomas and Bertie.
- Marion believing that the small engines were magical is similar to what James and Henry thought they were in Ballast from the Railway Series book Small Railway Engines.
- The way the other engines wake up Thomas is similar to the first series episode Thomas and Gordon, primarily its retelling in The Adventure Begins and just like The Adventure Begins, Henry tells Thomas that Gordon is waiting for his coaches.
- The Fat Controller saying to Thomas that he does not want to hear his excuses could be a reference to the nineteenth series episode, Who's Geoffrey?
- The second time Skiff tells Sailor John that they need to leave, the former sings part of the Banana Boat Song.
- In Never Overlook A Little Engine, there is a cake with "70TH" written on it; this is a reference to the 70th anniversary of the first Railway Series books.
- Duck saying that it feels like Donald and Douglas have been gone for ages is likely a reference to the fact that, when the special was released, the twins had been completely absent from the television series for seven years.
- Just before Thomas is seen chasing Skiff and Sailor John through the harbor, Toby's Series 2 bell can be heard as one of the sailboats' bells.
- Just after the scene where Ryan pulls over the pirate ship, in the shot of the boats in the harbour, Toby's bell from the second and third series can be heard faintly in the background. This is presumably meant to be the sound of a distant bell buoy.
- The Chinese theatrical release of this special also includes an edited version of the YouTube documentary 70 Years of Friendship, dubbed into Mandarin.
- This is the fourth known special dubbed into Hebrew.
- Sodor's Legend of the Lost Treasure was supposed dubbed into Finnish in 2015 or 2017, but for unknown reasons the idea was scrapped.
- The only special dubbed into Estonian.
- In both narrations, as Thomas approaches the construction site after his visit with Bert, Rex and Mike, he is humming Never Overlook a Little Engine.
- In the trailer when Sailor John watches Donald and Douglas bring the Pirate Ship to Arlesburgh Harbour, the sunlight was shown behind the lighthouse, but in the special itself, the sunlight is shown in the distance beside the town.
- On 1st June 2018, the songs from this special were released on iTunes, Spotify and other music streaming services.
- The special aired on Nick Jr. split into three half hour blocks on 23rd - 25th July 2018 by Mattel Creations. Also, because the nineteenth series opening was used, the credits that were used in the opening of the special were removed. Treehouse TV also airs the three-part version of the special.
- When Thomas is about to run into Toby and is switched onto the passing siding, Henrietta can be seen behind Toby. However, when Thomas is seen returning onto the branch line, Henrietta is missing.
- The digital release is slowed down to 24fps, which causes audio distortion.
- Annie's wheels are already moving before Thomas starts when they leave Ffarquhar.
- A hand can be seen through Percy's cab when he leaves Tidmouth Sheds. The same thing happens to Thomas in the first scene of "Never Overlook a Little Engine."
- When Emily brakes at Knapford, her bogie wheels spark, but these wheels are not fitted with brakes. Ryan's trailing wheels also briefly spark when he tries to stop the pirate ship.
- When Marion first sees Mike, his side rods are black.
- When Donald passes Marion at Arlesburgh Junction, the rivets on his smokebox are red.
- When Duck meets Donald and Douglas, he shunts some trucks and reverses slightly before greeting them. But at the end of the scene when the twins leave, the trucks have disappeared.
- Just before Thomas runs the red signal when he is chasing Sailor John and Skiff, he is on the right-hand track (from his perspective). But after passing through the tunnel, he is on the left-hand track for the remainder of the chase.
- Rex is missing his leading bogey for most of the special. His trailing bogey also disappears in one shot, as does Mike's leading bogey in a different shot when they tour Arlesburgh.
- Just before "Never Overlook a Little Engine" begins, Thomas' trucks disappear. Just after the song ends, the trucks have reappeared, but have moved further away.
- Just before the singing begins in "Never Overlook a Little Engine," Mike's mouth does not move when he says, "Oh".
- During "Never Overlook a Little Engine," when the Small Engines' drivers' hats blow away, Rex's driver's hat disappears for a split second.
- As the camera zooms out while the crew lays track, Douglas pulls into the shot, but Oliver's whistle is heard. Then, when Oliver pulls up and says "Here we are!" Douglas' whistle is heard.
- When Thomas arrives at the ballast hopper after taking on the bad coal, his trucks are already filled with ballast.
- When the narrator says "Marion was working on the next cutting," Jack moves without his wheels turning.
- When Thomas shunts the dynamite into the cavern, the trucks are still on the rails, but when the Fat Controller speaks from the hill and a shot of him looking down at Thomas is shown, the trucks have disappeared.
- When Marion is asking Thomas to guess what is in her shovel as he passes by, he is lower to the ground than usual, with his wheels clipping through the rails and ground.
- When Thomas stands up to Sailor John and shunts Skiff out of his way, his trucks are red. In a close-up, however, one turns green. In the next shot, they are all red again.
- When Thomas warns Ryan about the rope on the pirate ship during the chase scene, his paintwork is no longer scratched and dirty.
- When Thomas passes Gordon during the chase, the points are set to allow him to follow Sailor John, but they are never set back for Gordon, who passes over them moments later.
- Steam emits from Thomas' whistle when Gordon's whistle is heard during the chase.
- When the Small Railway Engines push the ballast trucks off the chute, the buffers on the chute's track disappear.
- When Sailor John drops Skiff's oar in the water, it does not make a splash.
- After Thomas says "It's good to be back, Annie," Clarabel has Annie's voice. In the same shot, Clarabel keeps laughing even when her mouth stops moving.
- When Thomas asks about Daisy at the opening of the branch line, Annie and Clarabel disappear.
- In the end credits, Gordon is missing his tender wheels.
- Christopher Ragland is credited in the UK credits despite none of his characters speaking in that dub.
- During his scenes at Arlesburgh Junction, Oliver's eighteenth series model is used. During the grand opening of the new branch line, his nineteenth series model is used.
- When Thomas pushes Skiff into the siding and Sailor John falls backwards, his hand clips through Skiff's sail.
- When Thomas arrives at Knapford to collect Gordon's coaches, Annie and Clarabel have their voices switched.
- When Ryan first arrives, Diesel can be seen in the background with some trucks. However, in a close-up of Thomas, the trucks disappear.
- During the branch line's ceremony, Donald is placed behind Marion. But when the engines leave for the harbour, Donald moves forward as if Marion is not there. A few shots later, he has switched to the same track as Douglas.
- After "Never Overlook a Little Engine," Rex is on the track right next to Thomas and is pulling some wool trucks, but two shots later, he is on a different track and pulling some ballast trucks.
- At the end of the special in the Brendam Docks scene, Salty is set back into his trucks, clipping through the one immediately behind him.
- When Donald comes round the bend before the unstable track, his train has no brake van, but in a close-up shot, his train gains one. Also before he rounds the bend, he has the number 10 on his tender, which is Douglas' number.
- When Thomas leaves to take his trucks to the dump, Ryan passes him and whistles, but no steam emits from his whistle.
- There are several mistakes in the German dub:
- Duck is called an American locomotive.
- Branch lines are called "Streckenabschnitte" (track sections).
- When Annie says "What new branch line?" she has Clarabel's voice.
- When Rex sings "Like Me!", he has Thomas' voice.
- When Ryan first arrives, it is said that he is supposed to work on the new branch line, but he is sent to Thomas' branch line.
- When Ryan collects Annie and Clarabel, the two coaches switch places from where they were earlier on.
- On the DVD cover and cinema posters, Ryan's smokebox saddle is purple, instead of black.
- When Thomas goes past the ship on display at Arlesburgh Harbour, the red lining on the back of his coal bunker is missing.
- When the small engines turn into butterflies in "Never Overlook a Little Engine," Mike and Rex's liveries have been switched.
- When Thomas is rescued from the water towards the end, Ryan's cab is not rendered properly, as the buildings in the background can be seen through his cab windows.
- At one point, the tracks leading up to the ballast chute at Arlesburgh Junction are shown to be Standard Gauge, when they are meant to be Minimum Gauge.
In Other Languages
- Sodor's Legend of the Lost Treasure
- Thomas and the Lost Pirate/The Sunken Treasure
- Pirate Treasure
- The Lost Ship
- Bert the Miniature Engine
- Pirate Ship Delivery
- Oliver and Oliver
- Sodor Dynamite Blast
- Pirate Cove Discovery Set
- Dynamite Ryan
- Mike the Miniature Engine
- Rex the Miniature Engine
- Bert the Miniature Engine
- Pirate Salty
- Lift and Load Cargo Crew
- Treasure Thomas
- Dynamite Delivery Accessory Pack
- Treasure Chase Set
- Thomas' Shipwreck Rails Set
- Hidden Treasure Set
- Thomas' Shipwreck Adventure
- Ryan and Skiff
- Looking for Pounding Treasure Set
- Skiff (original livery)
- Skiff (railboat tours livery)
- Treasure Thomas
- Pirate Salty