Koko is yearning for adventure - and she just might get it, as today the chuggers are making deliveries out of town. But Vee asks Old Puffer Pete to accompany them - and he's so SLOW. They always have to wait for him to catch up - and he's always letting off those embarrassing bursts of steam! During their travels, they come across a mysterious old spur track. Pete tells them it leads to Old Chuggington, which is now a ghost town. The trainees decide to explore the old town on their own and get helplessly, hopelessly lost. When Wilson accidentally sets off the old Chuggington Central Whistle, Pete puffs his way through the maze of tracks to investigate. He rescues the youngsters and takes them on a fascinating tour of the old town, which he still knows like his own pistons! The trainees realize that Pete isn't such a fuddy duddy after all and there's a lot that they can learn from him.