David Lindholm is found naked on his bed with bullets through his head and stomach and all the evidence points toward his wife Julia, but she claims that a woman killed him and took her son and when journalist Annika Begtzon is assigned to the case, she must work against the clock to clear Julia's name and find the missing child.

New York police detective Jacob Kanon searches for the killer of his daughter and her boyfriend, who were murdered while on vacation in Rome. Since then, young couples in other European cities have been found dead with little to connect the murders except a postcard to the local newspaper. Kanon teams up with the Swedish reporter Dessie Larsson, who has just received a postcard in Stockholm, and they think they know where to find the next victims....