When McGrowl saves the life of a neighborhood cat, the bionic superdog becomes a celebrity. McGrowl's original owner, the old lady, spots her former pet on TV and invites him over for a visit. So Thomas and McGrowl set off to the lady's house.Then their trip turns into a wild goose chase! The friends encounter many eccentric characters who send them from one weird and wacky location to the next. The mastermind behind it all is the Milton Smudge, who's determined to get McGrowl--no matter what! Thomas and McGrowl manage to escape unharmed, but Smudge vows he'll capture them next time...