Trouble starts brewing in Bikini Bottom when someone steals King Neptune's crown and the blame falls on Mr Krabs. Despite this, SpongeBob stands by his employer and sets out to find the treasure.

SpongeBob SquarePants comes ashore and embarks on an adventure to recover Krabby Patty's secret formula, which is stolen by Burger Beard, a pirate.

When SpongeBob SquarePants' beloved pet snail Gary goes missing, a path of clues leads SpongeBob and his best friend Patrick to the powerful King Poseidon, who has Gary held captive in the Lost City of Atlantic City. On their mission to save Gary, SpongeBob and the Bikini Bottom gang team up for a heroic and hilarious journey, where they discover nothing is stronger than the power of friendship.