Koko and the Tunnel

The trainees are heading for a lesson with Dunbar in the training yard when an underground tunnel catches Koko's eye. She wants to explore it but Vee says she isn't ready yet. Dunbar is called away from the lesson about switching tracks before they barely get started. With time on her wheels, Koko decides she's going to see where that tunnel goes. She persuades Wilson to come with her, and calls Brewster a 'scaredy-chugger' because he refuses to go. Koko and Wilson emerge into the countryside and Wilson starts to feel nervous in these unfamiliar surroundings. He wants to go home! Koko reluctantly agrees to go back, but they're in trouble - they can't switch tracks to turn around! Koko decides to steer over the switch with brute force. She derails and gets well and truly stuck. Back at the depot, Brewster is really worried and confides in Calley, who goes to rescues the young chuggers. Koko is really grateful. She's learned her lesson - she won't go exploring again until she knows how to be safe on the rails!