It's Spongebob's big day: the new Crusty Crab 2 is finally opening. The reason: Mr. Krabs likes money. But contrary to expectations, the yellow sponge is not appointed the new manager of the branch of his favorite restaurant because he is too childish. Dejected, he gives in to the will-less indulgence of Goofy Goober ice cream.
Meanwhile, the evil Plankton steals the crown from underwater King Neptune and blames Mr. Krabs for the non-existent crustaceans. Now Spongebob has to prove that he is no longer a child and sets off with his best friend Patrick Star in search of the missing crown in the forbidden city of Shell City. Will the yellow sponge succeed in retrieving the crown and saving Bikini Bottom?