This is the spin-off of the hit Disney Channel Original Series, "The Suite Life of Zack and Cody." The series follows twin brothers Zack and Cody Martin, London Tipton, and Mr. Moseby aboard the luxurious cruise liner, SS Tipton. While on the ship, the kids enroll in a semester-at-sea program, leaving Moseby in charge of the kids on the ship. The ship, owned by London's father, will cruise around the world, with tourists and students attending classes on Deck Eight- the one school that Mr. Tipton believes will make his daughter a better student. While living on the ship, expect Zack and Cody to still have their compass towards mischief.

After making plans to spend spring break with Bailey, Cody takes a job as an intern at a prestigious research firm, breaking his plans and leaving Bailey infuriated and refusing to speak to him. Zack then runs a billion-dollar submarine into Vancouver's seawall causing the equipment to get lost which results Cody being fired from the program and vowing to never speak to Zack again. While there, Dr. Olsen approaches Zack and Cody, telling them that they are perfect for the 'Gemini Project,' a massive project studying the effects of twins. After making much thought, the twins decide to participate, and land themselves among dozens of other twins. In the beginning, all seems normal, but before long, the two suddenly find themselves connected metaphysically in a way they never have been-able to before. If one twin has a thought, the other does as well; including feeling the same pain at the same time...