Meet Zack and Cody, 11 year-old identical twins and the newest residents of Boston's swanky Tipton Hotel. Living in a suite with their mom Carey, the boys treat the Tipton like their own personal playground.

Zack and Cody Martin are aboard the SS Tipton, a luxury passenger cruise liner owned by London's father. The ship cruises the world with tourists and students who attend classes at Seven Seas High, the one high school that London's dad thinks will make his daughter a better student. While out at sea, Zack and Cody still have their compass pointed towards mischief, and London learns to live a "fabu-less" lifestyle, including sharing a small room with Bailey, a country girl from Kansas.

Cody and Zack are approached to join the Gemini Project, a high-tech research center studying the dynamics between twins. Shockingly, they find themselves interconnected in a whole new way! When one twin experiences something, the other twin feels it too. This newfound revelation helps them see eye to eye for the first time, and it puts them in more danger than they could have imagined.

The exciting crossover event begins when Raven Baxter checks into the swanky Tipton Hotel while on a business trip with her designer boss. Zack and Cody get into the action when the models for Raven's photo shoot take a detour and Raven has a spooky premonition about the twins' fate. Meanwhile, Maddie comes up with a plan to get London to wear one of Raven’s new dresses. It almost backfires until London finds out that super pop star Hannah Montana wants a Raven original to wear on her new tour.