Based on a series of children's books, "Thomas & Friends" features Thomas the Tank Engine going on adventures with his fellow locomotives on the island of Sodor. Thomas is apt to get into trouble by trying too hard to be, in his words, a "really useful engine," attempting to do things that are best left to bigger engines. Other members of Sir Topham Hatt's railway include junior engine Percy, Thomas' best friend, who is always willing to help, and big engine Gordon -- the fastest and most powerful member of the team -- who uses his superior strength to help the smaller engines get out of trouble.