Sir Topham Hatt and his family are on Holiday and Toby was chosen to take them around Sodor, while stopping at the beach near Norramby Church Station Stephen & Bridget made a sandcastle modelled on a castle in the heart of Sodor and the intrigued Sir Topham Hatt asks Toby to take them to find it. Toby finds a split junction, with one track leading to the castle and the other to a mine. They visit the castle first and then the run-down mine. The mines are re-opened, but Toby is spooked by Thomas' tale of the "Old Warrior," who haunts the mines during the night. Toby is horrified to be put on guard duty at the mines and meets the "Old Warrior," but discovers that the ghost is really a narrow gauge engine named Bertram, who is given the nickname because of his bravery. The two become friends, Bertram is restored, and when the mine and the castle re-open, both engines bring visitors to the area.
Duke's old shed can be seen next to Bertram when he is discovered.
According to Britt Allcroft, Bertram was supposed to be a tank engine, but budget constraints forced the model crew to repaint Duke's model and use Smudger's happy face.
This episode marks the only appearance of Bertram to date as well as his only appearance in the fifth series.
The map of Sodor appears to actually be a map of North Wales.
Perhaps coincidentally, the real-world Ffestiniog and Welsh Highlighland Railways split at the town of Porthmadog. The FR goes to "the mine" at Blaenau Ffestiniog, while the WHR goes to "the castle" in Caernarfon.
The Munitions Factory, a station and the outer frame of the steel rig from TUGS appear as some of the old mine buildings.