Operation: K.A.S.T.L.E.

Numbuh 3 takes her little sister Mushi for a ride through the Rainbow Monkey Sugar Coated Castle of Love, but what promises to be a day of fun is ruined when King Sandy and his knights attack! The insane sovereign has never given up in his quest to marry Numbuh 3, and he threatens to destroy the Rainbow Monkeys unless Kuki agre