Terrible end to a wedding party: In the early morning, chief inspectors Eva Saalfeld and Andreas Keppler are called to a crime scene. A young, newly married couple, Annika and Peter, have been brutally murdered on the shore of a lake. The inspectors suspect the culprit among the wedding guests and ask them to submit a saliva sample to the headquarters. Florian Koll, a disappointed ex-boyfriend of the bride, does not follow this summons. When he tries to make incriminating evidence disappear, he is observed by the inspectors and is strongly suspected of having committed a crime. During their further investigation, Saalfeld and Keppler learn from the grandmother of the murdered bride that a family member was not invited to the wedding.
Between Annika's father and her uncle, thedriving instructor Horst Baumann, there had been a bitter argument years ago, as a result of which Annika's father died of a heart attack. The inspectors uncover a dark family secret. Shortly thereafter, Kerstin, a young high school graduate, is found murdered. As always, the photographer Roman Rustaveli takes pictures of the scene of the crime – behind the barrier. A cap Keppler found right next to the body could belong to his camera. Keppler notes that articles about both the bride and the high school graduate had appeared in the local newspaper prior to their murder—along with photos of Rustaveli. Eva, who knows Roman from her youth, investigates the man who seeks her closeness - a dangerous project.