Thomas the Tank Engine works at the Big Station, fetching coaches for the bigger engines. He keeps teasing Gordon the Big Engine, making him very cross. When the Shunter later accidentally forgets to uncouple Thomas from Gordon's coaches, Gordon decides to be really fast to tire Thomas out.

Edward is feeling sad, as all the other engines are bigger and younger than him. But when Gordon gets stuck whilst pulling trucks up a hill, it's Edward to the rescue.

Henry the Green Engine doesn't like getting his paint wet - so refuses to come out of the tunnel. The Fat Controller tries everything, including getting Thomas to push Henry out but the big green engine still does not move. In the end, the Fat Controller orders a brick wall be built to block the tunnel entrance, meaning Henry stays in the tunnel forever...

Henry is sad that he is stuck in the tunnel, and Gordon is having fun teasing him whenever he passes. One day Gordon's safety valve bursts just outside the tunnel. Edward is the only other engine available, but the train is too heavy for him. How could the situation possibly be resolved?

Thomas wants to pull a train instead of just shunting coaches for the big engines, who laugh and say he wouldn't be able to do it. One night Henry is ill, and next morning he still isn't better. He is due to pull the morning train, and when no other engine is available, Thomas has to pull the train. He is so excited, he doesn't notice until too late that he has started before being coupled to the train, leaving his coaches and passengers left stranded at the platform!

Thomas is bored, and when one night Edward offers to swap duties with him for the next day, Thomas takes up the offer. This involves taking Edward's trucks. However Thomas is not used to trucks...

Thomas is in the yard shunting when new engine James rushes past with a goods train yelling for help. James has wooden brakes and the trucks are pushing him down the line. The alarm goes - James has crashed into a field of cows. Thomas has to get the Breakdown Train and help James. Afterwards, the Fat Controller gives Thomas a very special reward.

James the new engine has to pull some coaches with the help of Edward. They do very well but James is so excited that he accidentally showers water all over the Fat Controller's new top hat! Later on he is pulling more coaches and bumps them so hard that a brake pipe is damaged. Newspaper and a leather bootlace could temporarily mend the problem, but only a passenger willing enough to hand over their laces will the train be able to continue...

James is feeling sad as he is still staying in his shed for being naughty. Eventually the Fat Controller lets him out to pull a goods train, but the trucks don't want to be pulled by James and misbehave. Whilst pulling them up Gordon's Hill, a coupling breaks and the last few trucks roll back down the hill. James goes to get them (they were stopped by the Guard) and starts on up the hill once more...