Lee Donghae and Lee Sungmin are brothers. Twin brothers. But they don't look alike. After several years in staying in the US, they decide to move away. They stayed inside a ship that travels around the world nonstop (unless it sinks). And also, their parents enrolled them into a school inside the ship. But they have to work for their own money. They meet their fashionista friend, Tiffany, which her father owns the ship. They meet again th