Captain E. Magination and his crew set sail to Mystery Island to find the buried treasure. They are followed by Captain Jack who plans to steal the treasure from them after they find it. Joined by totally awesome cruise director, Polly Wolly Doodle, the kids dance and sing their way though all the island has to offer, they defeat Captain Jack by squirting him with the milk of human kindness and everybody has a dance off. Turns out the treasure is really show costumes and the kids put on a show for Captain Jack who "hasn't seen a good show in years!" The adventure comes to an end with Captain E. Magination reminding everyone the even though things may be scientifically impossible, they're imaginatifically true!