Percy is annoyed when Thomas brags that he looks the best, so rubs it in when he gets showered with coal, but Thomas falsely claims it was his fault. Percy taunts him and Thomas doesn't warn him about weak buffers so he'll get struck too.

Gordon and Henry tease Edward when he loses a few freight-trucks while avoiding a pair of loose cows, but their claims of how they'd deal with cows are put to the test when one won't move off the railway.

Thomas' fireman's not being there prevents him from taking Edward's passengers, but he misses Bertie's trying to take them. Bertie is forced to put all his energy into trying to catch Edward to deliver them as he said he would.

Edward is teased by James about his weakness, but when his controls are tampered with and he goes out of control, James has to hope that Edward will be fast enough to pull him to a stop.

Trevor wants more work so is asked to help Thomas at the harbor, but Thomas doesn't know that he's moving stone around a blocked line and can't see the use of anything that doesn't run on rails.

Percy's playing pranks on Gordon and James cause them to hint about a railway-signal that doesn't exist, to confuse and trick him into making a mistake on the line.

Percy's new helper, Duck, is calm when Gordon, James and Henry try to boss him around. However, when Duck sees Percy's anger at their nature, Duck plans to outsmart the three big engines so they'll leave them alone for good.

Percy decides to compete with Harold, a loud proud helicopter, to a race after he scorns trains.

After getting back from being repaired, Thomas' brakes are weak and finally prove a problem when they don't completely stop him so he ends up taking off down the railway out of control.

Henry is annoyed to hear Percy carrying on about how well he performed a rescue despite a flood. Percy wants to go past the forbidden area at the harbor, despite Thomas' warning against it, and ends up sinking into the surf.

Hard-working Duck is unimpressed with the flattering trial-engine Diesel who claims there's nothing his kind doesn't know since they're so great. Duck challenges him to shunt, and Diesel runs into trouble when he tries.

Though Duck silences them, Diesel blames him for the freight-trucks' taunts. Henry protests that nobody confides in the trucks, so Diesel tells them jokes about the biggest three, saying they're Duck's, since the trucks want revenge.

Sent to Edward's station until the big engines' anger at him over Diesel's lies cools, Duck has to avoid a group of runaway trucks that try to force him into an accident.

The viaduct is being repaired and is causing delays on the Fat Controller's railway. One day, Thomas being late means he can help his friend Bertie the Bus.

Scottish twin engines Donald and Douglas arrive, making one extra for the Fat Controller to get rid of. Donald makes a break-van stop bothering Douglas, but has an accident, and Douglas is the one who tries to help James with the van.

Donald and Douglas are well-loved especially since they're a big help in winter, but worry that they will be sent away and turned into scrap. Edward suggests someone should talk to the Fat Controller, and the hard job falls to Percy.

Thomas arrogantly takes his driver's kidding seriously about how he could drive himself, and decides to try - and runs into trouble since he can't control himself.

With Thomas being repaired, a selfish, proud, lazy diesel named Daisy is called in to help Percy and Toby.

Percy hates doing the work Daisy doesn't so agrees to switch jobs with Toby for the day, but Toby's freight-trucks force him into an accident.

Bill and Ben the Twin Engines discover a group of their trucks missing and their drivers let them play a trick on the diesel who took them by mistake.

Gordon can't run on branch lines for safety, but acts like he's too good for them. One evening, a mistake sends him down the branch line and he has an encounter with Bill and Ben.

Edward has trouble even starting up, earning scorn from James and Gordon, but his biggest problem is when he has to put all his strength and determination into finishing a journey through a storm that damages him.

Percy is fascinated by a ghost-story his driver tells him, but Thomas scorns him before Percy finds out it was fake. Still annoyed for how Thomas spoke to him after an accident with lime, he gets Toby to help him play a prank.

Percy still teases Thomas for being afraid of his trick, but Thomas retorts by teasing him in any way he can. An incident with treacle and straw give him one more thing to tease him about.

On the way to pick up a Christmas tree, Thomas gets caught up in a snowdrift and avalanche. Donald and Douglas rush to rescue Thomas and the precious tree.