|This article is about 'the Big Blue Treasury'. You may be looking for 'the Big Yellow Treasury'.|
- Annie and Clarabel
- Sir Topham Hatt
- Henry (does not speak)
- Bertie (cameo)
Thomas is delivering tigers to the new wildlife park, but later on he sees a stripy tail moving in an old works shed. Percy sees two eyes looking at him and he goes to tell Thomas. The next day, his driver and fireman are reading the newspaper and hear that tigers had escaped the wildlife park. Thomas tells his driver to look in the old works shed. When they pass, they see the tiger and her cubs. They tell Sir Topham Hatt and call the keeper. The keeper thanks Thomas and names one of the cubs "Thomas".
Percy tells Thomas that his driver's birthday is next week. Thomas wants to know what a birthday is, so Toby tells him. Toby says that they should hold it at the station, so they could see the cake. Two days before the party, Thomas is sent to the big station to work in the yards and to stay with the bigger engines. Sir Topham Hatt arrives to tell Thomas well done. Thomas asked if he can go home and Sir Topham Hatt tells Thomas that he knows his secret. Back at the Ffarquhar Sheds Percy, Toby, their drivers, firemen, and some children decorate the sheds. Thomas arrives home, but no one is there. Then, the driver's wife stands in the door way holding a box and walks into the sheds. Thomas puffs in and everybody shouts "happy birthday". Then the driver's wife takes the cake out of the box; it looks like Thomas! Everyone climbs into Annie and Clarabel and the party begins.
A balloon show is coming to the island and James is taking the balloons to the show grounds. James wanted to stop and watch the show, but his driver says that they are late already. Later, while chugging down the line, James sees a balloon drifting down. James' driver slows and the balloon drops just in front of them. James' driver and fireman help load the balloon into one of the vans and the balloonists climb on board as they set off for the next station, where Sir Topham Hatt congratulates James.