Pete, a young orphan, runs away to a Maine fishing town with his best friend a lovable, sometimes invisible dragon named Elliott! When they are taken in by a kind lighthouse keeper, Nora, and her father, Elliott's prank playing lands them in big trouble. Then, when crooked salesmen try to capture Elliott for their own gain, Pete must attempt a daring rescue.

When the diabolical Professor Ratigan kidnaps London's master toymaker, the brilliant master of disguise Basil of Baker Street and his trusted sidekick Dawson try to elude the ultimate trap and foil the perfect crime.