On the remote island of Sandhamn, two mysterious incidents occurred. First, a body of an unknown man from the mainland was washed ashore—someone who had disappeared several months earlier. Then, in a hotel, the battered-to-death naked body of a woman was found, who turned out to be the cousin of the deceased. Inspector Thomas Andreasson, who survived a severe depression caused by a family tragedy, must unravel the connection between these two deaths. Why did relatives—strangers—arrive on the island one after another, and who could have been interested in their deaths?