Emily is a new steam engine who has recently arrived on the Island of Sodor. She accidentally takes Annie and Clarabel, and Thomas gets annoyed by this. Later, Oliver & Toad get stuck and Thomas is fast approaching! Emily, who is closeby, sees this and rushes to the rescue, but will she prevent a possible serious accident from occuring in time?

One day, Percy is travelling along Toby's old branch line and discovers the track is wobbly. He hurries back to the station to warn the other engines but gets frustrated when nobody listens to him. Later on, Thomas goes out onto the old line and gets stuck. Percy starts to worry when Thomas doesn't return home. Where could he be?

Fergus, a blue steam traction engine, goes to work with Bill & Ben in the quarry. But when he tells the twins to do things right, they become fed up and decide to do things wrong. This however gets them into trouble...

Skarloey is crossing an old bridge when he notices the track is out of place and can't stop in time, thus leaving him dangling above the river from a long way up. Rheneas comes and rescues him with the breakdown train and the bridge is soon repaired. But Skarloey is terrifed of using the bridge again and has to shunt trucks and coaches in the yard. Rheneas has to do Skarloey's work now as well as his own. But when he runs out of water due to puffing too hard, he ends up stopping over the first quarter of the bridge and now Skarloey has to overcome his fear and must cross the bridge to save him...

Edward is due to take the Brass Band to their annual concert, like he does every year. But he has an accident and has to go to the Works. Bertie fills in for him, but gets stuck. What will happen now?

Henry, lately, has been feeling sorry for himself as he's feeling dreadfully ill, but Thomas and Percy take no notice and don't believe him and decide to play a rather mean trick on him...

After hearing that the Queen of Sodor is coming, James volunteers to get her - but his happiness is short lived when the Queen turns out to be an old, dirty coal barge. James tries to do his job and stay clean in the process.

It's summer on the island and the refreshment lady wants to open a new tea shop. With the help of Peter Sam she looks all over the island for a suitable location to set up but simply can't decide where. But next day, is she in for a surprise...

A new tank engine from the LMS called Arthur arrives on the island. He has a spotless record which means he's never been naughty or left a mess. The Fat Controller puts him to work with Thomas and Percy. Arthur's first job on the island is to take a train of closed vans full of fruit to market. The trucks start to sing rudely and Thomas then plays a trick and tells Arthur that The Fat Controller doesn't like the trucks singing and that Arthur should stop them from doing just that. This soon leads to a terrible accident...

Toby is very fond of the windmill near the branch line. The windmill needs repairs after a storm and the miller can not afford to do so. Toby wants to help, and when he has to help clean up the lines from debris caused by the storm, he finds the solution to the miller's problems.

The old Scottish castle is reopening, much to Donald and Douglas' delight. Rumours start about there being a monster lurking in the waters near the castle, but the twins dismiss this as rubbish. One night, they get stuck near the castle - and in the water, something is heading towards them...

Rheneas is not too thrilled when he has to take a class of schoolchildren on a scenic train trip around the line but when he is accidentally diverted on an old branch line with sweeping bends and dips, his view soon changes...

Salty is hurt when Thomas and Percy tease him about how he talks, but when a lighthouse's light goes out, it's up to Salty and new arrival Fergus to save a ship heading for the rocks.

Oliver does not like snow - at all. When he has to make a delivery to a mountain village, the weather conditions mean he can't get back until morning. And when morning does come, Oliver receives quite an unexpected surprise...

The Fat Controller opens a new fishing route and chooses Thomas to run it; Arthur wanted to do so, but he wasn't chosen and Thomas doesn't even want to run it! However, all is resolved thanks to quite an incident later on...

A new park on the Little Engines' railway is being built. The final thing to add before the opening is a statue of an elephant, hence the name: "Elephant Park". Duncan is being impatient as usual and seeing as he is finished before the other engines, the Fat Controller orders him to take the elephant to the park. However, the foolish little engine realises too late that it's "Better safe than fast" when he leaves without waiting for the brakevan and is dragged down the line with the heavy load. Will he be able to stop in time?

Murdoch is a new arrival on the Island of Sodor. What he especially likes is a bit of peace and quiet. However, this isn't to be...

Fergus is tricked by Diesel and ends up in the Smelter Yard and when there instantly becomes scared and runs away. Will Thomas find him - or not?

Summertime has arrived on Sodor. There are more passengers arriving but less engines to do the work. Thomas calls this a "double decker" problem, which gives the Fat Controller an idea. He goes to see Bulgy (who has been a henhouse for several years) in his field to tell him that he'll be back on the road, helping to deliver passengers. Bulgy is delighted, but when he is cleaned and mended, the hens miss their old home and they creep aboard him one night, where they cause confusion and delay the next morning...

It is the time of year for the Summer Fete. Harold the Helicopter wishes that he could help too; but he's so busy with his patrol duties that he doesn't have time. This makes him sad. Later, however, his friend, Pegasus the Horse becomes stuck in a ditch and needs help. So Harold flies to the rescue by lifting him out of the mud and Pegasus is flown to the Fete - giving Percy quite a shock as to seeing what he thinks is a flying horse!

A new station is being opened and The Fat Controller and Lady Hatt have great difficulty in trying to get there on time. They are, however, grateful when they come across the "late comer" Skarloey.

All the engines are entering a competition to see which engine looks the fanciest and most eye attractive. But Gordon thinks it undignified to enter such a silly competition... until he has a slight mishap with a stray banner!

The Duke and Duchess of Boxford pay a visit to the engines, and bring with them Spencer, their own private engine. He is sleek, shiny, fast and full of pride. Gordon is jealous and feels that he is not the fastest engine anymore. However, disaster strikes when Spencer runs out of water! It is up to Gordon to save him and redeem himself of his stolen title.

It's Christmas time, and Elizabeth gets sent to collect a shipment of Christmas puddings from the docks. But Thomas is jealous and feels sure he would be better than Elizabeth at traveling through the snow. On her journey, the shipment is so heavy Elizabeth gets stuck in the snow...

Rusty is pulling a train across the old wooden bridge when he notices that some of the joints are loose. He goes and tells the Fat Controller who closes the bridge until it is mended. Rusty then tells the other engines, but Duncan thinks Rusty is just being a silly little diesel and puffs away without refilling with coal. Later on Duncan needs coal, and the only coal available is across the bridge, so off he goes. But Duncan runs out of steam halfway across and can't move, and then the bridge starts collapsing...