SpongeBob feels neglected by his friends and decides to leave Bikini Bottom. Along the way, he accidentally bumps his head and loses his memory. SpongeBob wanders away into a new place called New Kelp City and attempts to get a new job, unaware he is becoming a target for a criminal gang known as the Bubble Poppin' Boys, while Patrick, Sandy and a reluctant Squidward try to find him.
