On a walk along the Northumberland coast, Dutch vacationers come across the remains of a body. An old life jacket suggests a link to an accident that happened 21 years earlier, when a sea tug, the Pollux, sank north of the dune island of Rottumerplaat. In a complicated mission involving the sea rescuers from Ameland and Norderney, all of the crew members were rescued – except for the captain. Is the recovered skeleton the missing man?

Inspector Liewe Cupido, known as „the Dutchman,” wants to pass on the case, as he is currently preoccupied with his own past: the mysterious disappearance of his father at sea. But when his investigating colleague Xander Rimbach is poisoned on Norderney, the taciturn detective’s interpersonal intuition becomes indispensable.