Season 12

It's Knapford Station's birthday and all the engines are preparing for the festivities. When a photographer comes to photograph the engines for a billboard Diesel accidentally obscures Thomas; Thomas thinks this was on purpose and is so distracted he goes the wrong way and knocks the billboard over. This gives an opportunity for all the engines to be in a new photo, but when Diesel isn't told, he has to do all the others' jobs. Everything is soon rectified and the new photo is put up at Knapford.

Edward is told to take a brass wheel along the express line to the Waterworks, but opts to take the branch line so the people can see him. Although Edward is warned the line ahead is bumpy, he continues onwards as the school is nearby. When the wheel begins to tear the rope, Edward goes up Gordon's Hill, but then the wheel rolls off to the Smelters. Edward saves it just in time and has it chained on so it won't fall off.

The carnival is coming to Sodor again, and Rosie wants to pull the train, but she is told to be the back engine for Emily. Rosie decides to take the train so that Emily can do her other jobs, but the couplings keep breaking and crashing- unbeknownst to Rosie

Peter Sam rushes his jobs in order to hear a tale about Proteus from the famous storyteller, Miss Marvel and crashes into a statue of Proteus! He tries to bring the statue to storytelling and redirects his friends, but his carelessness leads to trouble.

A storm has hit the wishing tree, so some woodsmen are to be brought to the island to prop up the tree. But Henry thinks that the woodsmen are chopping the tree down. So he takes Toby, Thomas, Percy and Emily's loads to block the lines, leading to the tree. Harold eventually informs Henry that the woodsmen want to save the tree, so Henry delivers the loads to their destinations, and the woodsmen arrive at the forest to save the tree, with some help from Henry.

When a big, brash engine called Hank offers to help Thomas with his chores, the little engine shrugs off his assistance.

Toby wants to make an impression by searching the island for something special. But when Toby is taking workmen to Great Waterton, he spends to much time looking for something special, he eventually runs out of coal. But when he finds a metal piece lying beside the track, Rocky lifts it of the ground and Toby finds the sign of the 'Great Waterton Tram Shed'.

Emily is the only one who finishes her jobs on time, and thus is called "Excellent" by the Fat Controller. She is then given a job to take Trevor from Farmer McColl's farm, to the Airport to clear some rubble before Jeremy the Jet Plane lands, who is carrying The Fat Controller's Mother. Murdoch, Thomas and Duck inform Emily that some tracks are not safe, Emily ignores them, which lands her into trouble when he track on a muddy dip, sinks. Murdoch helps her out and Emily, who arrives at Farmer McColl's to take Trevor, now asks Murdoch to use which tracks, and delivers Trevor just in time, as Jeremy descends onto the Airport, with The Fat Controller's Mother.

Freddie decides to organize a winter party at the wharf instead of at Mr. Percival's house, so that Colin the Crane can join in, but neglects to tell Mr. Percival and so the equipment is loaded onto a barge. Freddie eventually tells Mr. Percival about the rearranged party, to which Mr. Percival agrees on. Freddie stops the barge just in time and the party is now on the Wharf. Colin thanks Freddie for his help.

Thomas has to take a fireman to Maithwaite for a medal ceremony and decides to try and help the engines on the way - although all his attempts end in failure, when Rocky drops a water tower, Harvey goes down the wrong line and Gordon can't find Toby. Thomas asks Percy to collect the fireman and sorts out the mistakes that he has made. He finds Bertie, broken down on a muddy road and agrees to take children to the medal ceremony. Thomas feels that he is now a real hero.

It's the Percival twin's birthday, and Duncan is to give them a special birthday ride, just as he always does. Duncan is getting his special birthday flag fitted, just as the Thin Controller, Mr. Percival, arrives with news. He asks Duncan to collect a hot air balloon from the Transfer Yards. The twins will be getting a ride in a hot air balloon for their birthday.

It's winter on the Island of Sodor and James, Thomas and Stanley are shunting trucks at the yard. James shows off that he can shunt Hector to the back of his train. He puffs away with his trucks, which he has to take to Great Waterton. On the way he Harold tells James that he has to take the longer route. But James gets cross and takes the snowy track. He takes the wrong route when he sees Edward who tells James to take the longer route. But James doesn't listen and Hector tells James what to do. He doesn't listen again and his trucks gets stuck in the snow. So this time, James does listen to Hector and make his trucks go through the snow. He, Hector and the Trucks, soon make it to Great Waterton.

Toby is the first to lead Great Waterton and Thomas is pleased for his friend. But when he arrives at Great Waterton he is surprised to see a new steam tram, Flora. He feels Toby will be upset so tries to keep her away from Toby. She soon runs out of coal and then Toby reveals he was nervous about leading the parade alone, so Thomas then has to put things right.

While working at the Quarry, Diesel challenges Thomas to race backwards around the Quarry, but causes Mavis, Arry and Bert to bump off the rails. Henry arrives to collect his trucks, which Thomas and Diesel were supposed to have loaded with Quarry stone. They eventually finish the job, then have one more race, forwards, as they arrive together at the finishing point.

Gordon boasts to Stanley that he never gets lost. He and Stanley must arrive at Great Waterton, whoever arrives first must take important people, and whoever arrives second must take workmen. Gordon wants to take the important people, so he takes some shortcuts, but gets lost while refusing to be helped by Duck, Oliver and Toad. After an accident with Ben's trucks of logs, which make their way down onto a line, he then asks Ben for help to take the right tracks, with the addition of Oliver, Toad and Duck. He arrives on the line to stop Stanley from hitting the logs, he succeeds, and Gordon now wants Stanley to take the important people.

Thomas and the narrow gauge engines must collect presents for Mr. Percival's birthday. Sir Handel is to tell Mr. Percival and everyone else his 'Man in the Hills' story. He tells the engines that the man is white and has never been found. Thomas believes that he can find him, but fails when presuming that the 'Man in the Hills' is a Baker, or a Miller. He then takes them back to make Mr. Percival's cake and tells Freddie to find the 'Man in the Hills'. Thomas soon finds that he is carved onto a hill for everyone to see. Everyone arrives for the party, as Sir Handel tells everyone his story about the 'Man in the Hills'

Thomas is worried about his brakes as they make funny noises. While ordered to deliver bricks for the repairing of the Sodor River Bridge, Thomas goes on a bumpy tracks which makes the bricks fall out of his trucks, Thomas doesn't know this, then while trying to brake on Gordon's hill, hits some emergency buffers, as more bricks fall off. Thomas finally makes his way to the bridge, but his brakes stop working all together and finds himself dangling on top of the gap of the bridge. With the help of Stanley, Rocky and Murdoch, they recover the bricks and Thomas has his brakes fixed at the yards. He comes back to the River Bridge to thank Stanley for his help.

A New Bandstand is being built at Great Waterton. Sir Topham orders Percy to collect Lady Hatt, but not tell her where she is going. But Lady Hatt asks Percy to take her to her favourite places.

The puppet show has arrived on Sodor and Skarloey is determined to pull the special train

Neville informs Thomas and Percy that the brass band is coming for a special concert. Thomas suggests that if Percy wants to collect the band then he should go to the washdown, but while Percy is away the Fat Controller arrives and asks Thomas to take the band. Thomas feels bad and tries to avoid Percy, but when he has to collect the band from Brendam he is found by Percy. Thomas, guilty, asks the Fat Controller to let Percy collect the band afterwards, and leaves to tell Percy of his plan. Percy and Thomas make up, and agree to never keep secrets from each other again.