Kelly's grandpa invites the whole gang to his little hotel "The Hideaway" in Hawaii for summer vacation. They expect a marvelous time at the beach - without Belding. Upon arriving, they quickly learn that not only is Belding there, but they also have to help Kelly's grandpa from losing his hotel. Meanwhile Zack meets (again) the love of his life, Jessie and Slater bet with Lisa that they won't fight, and Screech gets kidnapped by the Pupuku clan.

Lovable schemer Zack Morris leads his pals on adventures at California's Bayside High School. The friends navigate relationships, final exams, school dances, breakups and more while frequently frustrating their principal, Mr. Richard Belding, who does his best to keep them in check.

In the quiet waters of the Mississippi, body parts are being discovered. No one knows what is behind it all, until a huge man eating bull shark turns up. This bull shark is different, as it can breath in fresh water, making a deadly encounter between anyone who comes before it. John Sanders must now try and reach the surface, with his ex-wife and whilst being held hostage.