Air date: October 15th, 1986
Percy works in the yard, collecting coaches and trucks that the bigger engines need for their trains. Although he works hard, he can also be very cheeky. One day, he wakes Gordon up by telling him is train is ready. Gordon jumps, thinking he's running late, only for Percy to reveal a line of dirty trucks. Gordon is angry and tries to think of a way to pay Percy out.
Percy then goes to James and tells him that the Fat Controller has sent a message for James to not leave the shed. James is delighted, thinking the Fat Controller wants him to pull a special. As a result, he refuses to leave the shed when his driver and fireman try to make him move. The other engines are angry over having to do James' work as well as their own. Finally an engine inspector arrives and tells James to move. James refuses and tells him about the message the Fat Controller sent. The inspector points out the Fat Controller didn't send a message as he's away for a week. James is horrified and quickly leaves to find Percy, but Percy had decided to make himself scarce. When the Fat Controller comes back, he does see James and Percy too, telling them both off for causing trouble.
A few days later, Percy is showing off to Gordon and James as the Fat Controller has asked him to take trucks to Thomas' junction. He's boasting that he was chosen as he's a really useful engine, but James thinks he probably just wants him out of the way. Gordon and James then put form a plan and put it into action. They claim they were talking about being careful with the signals at the junction, especially "backing signals". Percy, keen to show off, claims that he knows all about signals and leaves, but worries as he has never seen or heard of a backing signal before.
Soon Percy arrives at a signal set to danger. However, when its arm moves up instead of down, Percy, having never seen anything like it before, guesses that it's a backing signal and begins reversing. Percy's driver is shocked and quickly stops him, but Percy insists that it's a backing signal and tells his driver about what Gordon and James had said. The driver laughs, then tells him the truth. Percy is eager to leave before he is seen, but is too late, Gordon goes past and sees that Percy fell for the trick. Percy quickly and quietly finishes his work.
That night in the sheds Gordon and James talk about signals; while they think it's funny, Percy thinks they're being very silly.
Tropes featured in the episode:
- The UK narration states that Gordon thought how to pay Percy out. However, in the US narration, it states that Gordon thought how to get back at Percy for teasing him.
- When The Fat Controller comes to see Percy and James, the UK narration states that the engines wished he hadn't seen them; the US narration states that he was cross with the two for causing so much trouble.
- In the scene after the above example, the UK narration states "One morning, Percy was careless", but in the US, it says "But at the very next day, Percy was still being cheeky.".
- Bratty Half-Pint: Percy.
- Break the Haughty: What Gordon and James do to Percy.
- The Freelance Shame Squad: The episode ends with Gordon and James teasing Percy for falling for the signal trick in the sheds.
- Gullible Lemmings: Percy easily falls for Gordon and James' trick of backing signals.
- Karmic Tricksters: Gordon and James.
- Oh, Crap!: This was Percy and James' reaction when The Fat Controller came back and was mad at them for the trouble they caused.
- The Prankster: Percy. This didn't end well after tricking James, however.