Duncan and the Old Mine

Duncan and the Old Mine is a ninth season episode.

Plot
Duncan is looking forward to take holidaymakers to see Culdee Caves when his job is given to Bertie instead. Mr Percival wants him to work with Rusty delivering coal trucks to the transfer yards for Thomas as the machines at the coaling plant have broken down. On his way to the coal mine, Duncan sees an old line leading towards some bushes and, ignoring Rusty's reminder that they have work to do, he goes down the old line which leads to an old mine entrance. Carelessly, Duncan crashes into a roof support, causing the entrance to collapse behind him! Duncan carries on into the mine until he hits something, which he thinks are buffers - until he hears a squeaking noise and realizes that he ran into some coal trucks. Pushing the coal trucks, Duncan finds that the mine shaft was actually a mine tunnel when he arrives at a bordered-up exit, and then, he pushes the trucks out of the mine. Rusty, who had being looking for Duncan, finds him with the coal trucks, so they take it down to the Transfer Yards where Mr Percival tells Duncan that he must think clearly when he wants to have another advenuture.

Characters

 * Thomas
 * Rusty
 * Duncan
 * Mr. Percival
 * Mighty Mac (cameo)
 * Bertie (mentioned)

Goofs

 * Rusty was referred to as a girl in the first American narration.
 * In the scene of the trucks approaching the boarded-up exit, after they stop a shadow moves across one side of the door, possibly the hand of a crew member that was pushing the train.
 * The mine that Duncan went into wasn't really a mine. If it was a mine, it wouldn’t have come out on the other side of the mountain.
 * The points switch back to Rusty's line after Duncan went onto his line. They also seem to switch for Duncan as well, as he was supposed to be on Rusty's line, and he went onto the other sealed-off line.
 * When Rusty and Duncan arrive at the Transfer Yards, the truck behind Rusty is derailed.