Sidney has to go and collect Percy's new wheels, but his memory is not very good. Thomas suggests that Sidney to make up a song to help him remember.

Percy still remembers the time he raced against Harold the Helicopter. One day, he is bringing letters to Santa, and thinks that Harold is calling him slow and out of date again, and decides to not listen while he tries to make up for lost time due to the snow.

Philip thinks that Toby is a boxcab just like himself and wants to become friends, but Toby is not so keen on doing the same thing as Philip and finds him rather persistent and overwhelming, by having a race to the Ffarquhar Quarry.

When Henry is given the job of pulling the express, Gordon goes on strike. Passengers start saying that Henry takes the express even more gently than Gordon does.

Devious Diesel is known to be mean against the other engines on Sodor, and that is how his diesel friends like it. One day, Thomas spots Diesel being friendly with some ducklings, and threatens to tell everyone whether he is mean or not.

Thomas has trouble with the Troublesome Trucks yet again in the yard. When Samson arrives with a goods train, his brake van, named Bradford, sees Thomas and offers to help.

Samson comes to Sodor to help out with bringing stone from the Blue Mountain Quarry.

Despite being different from each other, Ryan and Daisy work together on the branch line between Harwick and Arlesburgh.

Daisy does not think she would ever need Annie and Clarabel when she is tasked to take care of passengers on Thomas' Branch Line while he is put on quarry work. But one day, she does need them due to her popularity among Thomas' passengers.

Snow has arrived early to the Island of Sodor, and Donald and Douglas work together to clear the tracks. While at a junction, they have a choice: to clear Thomas' branch line or clear the track to the Search & Rescue Centre.

James is a mixed traffic engine on the Island of Sodor. He likes pulling coaches more than trucks. A few times, he shows off too much, and wants to be the centre of attention.

A heavy storm is arriving at the Island of Sodor. At Arlesburgh, Skiff's new captain, Joe, checks that everything is secure. Duck and Oliver are just finishing their passenger runs, and tease Skiff for being a little rail boat.

Sir Topham Hatt gives Daisy a special, to bring some entertainers for a performance. Daisy is excited, and boasts that the entertainers would choose a railcar like her.

Thomas enjoys the competition of Max and Monty but begins to question his friendship as Max and Monty mess about while working, affecting Thomas' work.

Connor boasts of being the fastest engine, but one day, he breaks down on the Island of Sodor and goes to the Steam Works to be repaired. Connor starts to worry it will happen again if he goes too fast and after that, Connor becomes the slowest engine on the island.

James is asked to take the Mayor of Sodor and Sir Topham Hatt to a party at Callan Castle, but has to do other jobs first and every job he does, he gets dirtier and dirtier.

One sunny day, the tracks buckle and bend and Dowager Hatt gives the Fat Controller a new hat, which everyone calls a safari hat. The Fat Controller gets sick of everyone teasing him and tries to find a way to get rid of it.

Some visitors come to the island to take photos of engines. They visit the Arlesdale Railway and take pictures of the small engines, but Bert is cross that they will not take pictures of him.

Duck's driver boils an egg in his whistle, which is now clogged and makes a funny noise. The engines tease Duck about his whistle, especially Mike who says engines without whistles are improper engines.

Mike is annoyed of always being stuck behind animals, Rex boasts to the small engines about how easy wool deliveries are.

Henry is accidentally given some "Glow in the Dark" paint at the Steam Works and is confused as to why everyone he comes across runs away from him. It is shown that his paint is glowing and laughs at the misunderstanding.

One night, Percy is frightened by a strange sound from under the bridge at the Watermill. Toby is worried, though Thomas does not believe it to be true, until he too hears the sound.

When a rail Zeppelin called Hugo comes to Sodor, everyone at first is very impressed. However, Stephen is concerned they will be replaced by engines like Hugo, making the engines worry about their future. They take their anxiety out on Hugo, making him feel unwelcome.

After word of an airship resembling Hugo spreads, Hugo feels he should be able to fly just like it. He gets some encouragement from Skiff and tries to take off into the sky like an airship on Gordon's Hill, like his non-rail aerial counterpart.

Judy and Jerome are upset that they are never taken out any more as Rocky is now the official crane of the island. Ryan, who feels sorry for them, takes Judy and Jerome out for a change of scenery.

Skiff hears word of a mermaid statue arriving at a museum at Arlesburgh Harbour, believing it is real.

Diesel now meets up with two other ghostly engines. The Ghost of Christmas Present and the Ghost of Christmas Future, and he later finds Sir Topham Hatt still at Knapford during the Earl's Christmas party at Ulfstead Castle.

Thomas is sent to take a special crate to the Town Square from the docks, but Cranky accidentally drops the crate.

Kevin gets stuck out in the snow, and Victor goes out looking for him, despite his hatred of snow.

Toby accidentally runs out of coal at the scrapyards, leaving the engines to think he's going to be scrapped.

Sir Topham Hatt is anxious as two grumpy inspectors have come to inspect the railway, starting with Thomas. To prevent an even worse report, Thomas helps return the lost pocket watch to the railway inspector.

After he sees Sir Topham Hatt's grandchildren with chickenpox, Henry worries about catching the disease himself.

Toad spots a stranded whale on the beach, but Oliver does not take him seriously.

Percy doesn't notice his sheep jumping out of his cattle truck.

Henry becomes paranoid of meeting an abominable snowman after Spencer teases him about it.

Salty's imagination runs away with him as he worries about going to the Mainland by sea.

Diesel starts causing trouble at Christmas time and he gets visited by the Ghost of Christmas Past.

Diesel now meets up with two other ghostly engines. The Ghost of Christmas Present and the Ghost of Christmas Future, and he later finds Sir Topham Hatt still at Knapford during the Earl's Christmas party at Ulfstead Castle.

Mavis has an accident at Ffarquhar Quarry and is sent to the Dieselworks. Den is sent to take her place, while Dart has to stay at the Dieselworks. However, the two always work together and they fear to be without the other.

Thomas feels guilty about causing Hiro to have an accident. To make up for it, Thomas ventures into Hiro's old hideout to see if he can try to salvage some left behind parts.

Stephen is a slow engine, but one day, when the Sodor Suspension Bridge collapses, he tries to stop Gordon from crossing the bridge.

Thomas, Spencer, and Bertie argue over how many wheels are best.

Thomas and James compete with each other to see who can get to Dryaw first.

Emily idolises Caitlin when she sees how fast Caitlin can go.

A new diesel boxcab named Philip arrives. Loving to race, he thinks he's racing Gordon when in actuality Gordon never took part.

James is determined to prove himself stronger than Philip, but he ends up crashing on the stone bridge.

A mother and her noisy baby want to have a ride on Thomas' train, but the baby keeps crying which leads to irritation to Thomas, Annie, Clarabel, and the passengers.

Rocky ends up derailing and the Search and Rescue Team have to work together to put him back on the rails again.

Thomas discovers Bertie's been rerouted to behind the other side of the mountain, making Thomas curious as to what's there.

Bill and Ben say that Timothy is no help at all and send him to help Cranky & Porter at the docks.

Percy overhears some workmen talking and thinks Sir Topham Hatt is leaving Sodor, so he and the other engines go on strike at Tidmouth Sheds.

Diesel is jealous of Percy's job to collect the Mayor of Sodor, so he directs Percy to an old disused quarry while he takes him himself.

Marion rediscovers Glynn the Coffee Pot Engine, who restored and taken to Ulfstead Castle.

Stephen becomes jealous of all the attention received by Glynn at the castle.

Daisy's springs need fixing after Diesel bumps her and when the rumours spread about Daisy not being able to be mended, Diesel begins to worry.

Diesel causes trouble between Daisy and Harvey by spreading rumours.

Terence takes a shortcut across a frozen lake while collecting Christmas trees.

Spencer and Gordon upset their passengers when their competitive behaviour gets out of hand.

Daisy is disappointed when her Christmas does not go exactly as planned.

Dowager Hatt runs the railway while Sir Topham is away, but causes confusion and delay.

Emily gets stuck in the middle while helping Donald and Douglas.

When a big freeze hits Sodor, Diesel finally proves himself to be a hero.

A branch gets stuck in the gears of Harvey's crane, but he does not want to make a fuss about it.

After mocking the way she was speaking up for herself, Stephen thinks that Millie ran away after hurting her feelings.

Sir Topham Hatt's new public address system causes havoc at Knapford station.

A new coach temporarily replaces Henrietta while she is at the works.

Cranky thinks he will be replaced by a big, new, fancy crane.

Cranky competes against Carly the new crane when she starts taking all his work and both of them get quite the surprise at the end of the day…

Thomas starts making unscheduled stops for his passengers, which in turn delays others.

Philip tries to discover why he has the number 68 painted on his side after being teased about it.

After Rosie is repainted red, she and James have a race.

Edward searches for a new shed while his berth at Tidmouth is being repaired.

Thomas is in China taking passenger trains with An An and Lin Yong, where he gets into trouble while racing with Hong-Mei, another blue tank engine, and the number 1 engine in China.

With all the changes being made to the railway, such as Edward and now Henry leaving Tidmouth Sheds and Nia staying in Edward's place, Gordon is feeling a little blue, so Nia has to help him get used to it.

A new tender engine named Rebecca comes to work on the North Western Railway, but gets clumsy and blocks the Flying Scotsman's platform at Vicarstown early, makes her passengers late by leaving the stations early, and blocks the engines down at Brendam Docks.

While working on the Indian Railway, seeing new places, finding animals all around on the lines, and meeting Rajiv, Noor Jehan, and Shankar. When Thomas derails in a muddy pond, he is very surprised when an elephant comes to his rescue.

After admiring Belle's water cannons for putting out fires, Marion's steam shovel for digging holes and playing games, and Harvey's crane hook for lifting crates, Rebecca is worried that, unlike the other engines, there is nothing special about her.

When an action movie is filmed on the Indian railway, Thomas is desperate to be involved.

Yong Bao informs Thomas about Pandas as the national animal in China, so he looks hard for one in the bamboo forests while taking the film crew, An An and Lin Yong to the Nature Reserve.

Thomas is pulling a truckload of coconuts to the Indian Railway Station for Charubala and her friends when he encounters some cheeky monkeys at the Monkey palace, despite Rajiv's warnings.

After a crash at the back of Tidmouth Sheds for showing off, a sad James is waiting at the Steamworks to be repaired. He hears that there might not be enough red paint to repaint him and gets worried he will be repainted a different colour.

Shane shows Thomas the Outbacks of Australia, leading Thomas to take his coaches, Aubrey and Aiden, and some passengers on the Outback tour, only to take a wrong turn and get stuck on a high bridge.

When a storm destroys a classroom at Harwick School, Duck tries to find a coach to take the children in, but fails when everyone seems unable to spare a coach.

When Ashima tells Thomas that tourists come to India to try to see tigers in Noor Jehan's tiger safari trains, he wants to see the tigers too.

Thomas' friend Merlin comes to Sodor from the Mainland for the first time, and Percy wants to see him.

James starts to bully Philip and not say sorry to him. But when Philip takes the Troublesome Trucks of sardines over the fenland track, James blocks his way and causes Thomas, Paxton, and Rebecca to stop behind them.

Thomas thinks he has been given very silly cargo until Hong-Mei explains that it is a very important water wheel, made from bamboo, but Thomas loses it while taking a shortcut and tries to get it back.

Samson is terrified of fireworks, as Thomas finds out, and when Samson mistakes the sound of Cyril the Fogman's warning detonator for fireworks, he is so frightened that he races off with Bradford into the fog and gets lost.

Thomas tries to save one of the Troublesome Trucks of China, named Lei, but fails to do so. Yong Bao teaches Thomas all about tai chi, and Thomas soon uses it to rescue Lei, who is racing down the tracks again.

It's Christmas and the boiler at the Animal Park breaks down, so it's up to Thomas and the Steam Team to find a way to keep the animals warm.

Thomas wants to be just like Isla, a Flying Doctor's plane, who transports Dr. Claire to remote places where it is hard for patients to get to hospitals or doctors for treatment, but fails to do so. When a cyclone come in, Thomas is determined to save the day.

Thomas is in Australia for Christmas, and is disappointed that it is different from Sodor due to no snow. But in the meantime, he must help a little girl named Madeleine retrieve her toy kangaroo from a real one.

Thomas is terrified when he is given the honor from Yong Bao of bringing a dragon to the Chinese New Year celebrations, thinking it would be a real fire breathing dragon.

During Valentine's Day, Thomas and Rosie try to avoid each other after Diesel, Bill and Ben tease them for being "special friends", but they must come through their fears when Sir Topham Hatt asks them both to prepare his Valentine's Day surprise for Lady Hatt.

Sidney is shunting a flatbed of engine parts, but he cannot remember what he is supposed to be doing with them since Diesel jolted his memory. Paxton thinks this sounds like a kind of mystery that can only be solved by a Special Agent.

Thomas offers a lift to a ranger named Ranger Jill while working in the Australian Rain Forest. Thomas is excited to learn from her about all the animals that live there, but he is too loud and impatient to be very useful.

Nia is a really clever engine and knows about all sorts of things, but when the Fat Controller asks her to take Annie and Clarabel and pick up passengers from Knapford Station to Thomas' Branch line, Nia has great trouble reading numbers so Annie and Clarabel teach her.

Bill and Ben's latest game consists of hiding trucks and making other engines look for them. But when the twins hide a van full of Sir Robert Norramby's Christmas supplies for Edward to collect, they try to return it, but have to travel all over Sodor to look for it.