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.