The experienced art thief Vincent has stolen the multi-million Russian painting "The Black Square" - his last big coup before retirement. The painting is to be handed over to the buyer on a cruise ship. As the procurement of tickets and forged passports fails, Vincent and his young henchman Nils overpower two passengers shortly before the ship sails and take their places. But it turns out: the supposed holidaymakers were supposed to perform on board as David Bowie and Elvis Presley impersonators. Promptly, the misjudged artist Vincent and the kleptomaniac Nils have to replace the two entertainers. Desperate to maintain their cover, they improvise their way through the daily stage program. But they have not done the math with the other crew members. The on-board pianist Mia and the gentleman host Levi find Vincent and Nils highly suspicious. Despite their efforts not to be discovered, soon not only Mia and Levi are on their trail, but also the crew manager Helen and the head of security Bernhard get wind of their true identity - and of their valuable stolen goods. Nils is finally unmasked, and Vincent is so in love that he doesn't notice that his acquaintance from the on-board bar, the arty Martha, is only seeking his proximity and sitting for him because she too only wants one thing - "The Black Square". On board, a wild cat-and-mouse game breaks out through the world of art lovers, thieves and swindlers, of timid love and dazzling shows, of forgeries and intrigues - but who has the real "Black Square" in the end?
