Chuggington - Series 1 - Koko and the Tunnel

Children's animation set in Chuggington, a special place where all the trains are known as chuggers. They talk, think for themselves and don't need drivers! Ride along with young trainees Koko, Wilson and Brewster as they embark on new adventures, make new discoveries and learn the true meaning of friendship. 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. When no one is looking, Koko decides she's going to see where that tunnel goes...