The idyllic summer tranquility of Sandhamn is shattered when a student, Marcus Nielsen, is found dead. Everything indicates suicide. His mother has a hard time processing what has happened, and can't believe that he would take his own life. Detective Thomas Andreasson and his partner Mia Holmgren with the Nacka Police become involved and discover that Marcus had several meetings scheduled with different people. They interrogate his supervisor from the university and she seems to know more than she is willing to say... As they learn more about Marcus, it becomes clear that he was murdered. When another man is found dead in his bathtub, it raises the question of a possible connection between the murders.