On a sunny day at Lake Chiemsee, children stumble upon a man's body on a sailboat, prompting Kommissar Hattinger and his Prien police team to launch an investigation. Soon after, a second murder is discovered: Annette Kaufmann, a writer, has been killed in her vacation home. As the detectives delve into the cases, they uncover connections that lead them down a path of intrigue and mystery, testing their skills and the bonds of their community. They face a race against time to piece together the clues before the killer strikes again.