During a routine check, two police officers accidentally come across Gabriel Engel (André Hennicke), a brutal psychopath who is suspected of having killed more than 15 male youths by bleeding them and painting religious pictures with their blood. A spectacular shootout ensues, in the course of which the reinforcements called in, led by Inspector Seiler (Heinz Hoenig), succeed in arresting the serial killer. During the subsequent interrogations, however, the hard-nosed Seiler fails due to Gabriel's cold-bloodedness. The developments in the Engel case are also followed with excitement in the small village of Herzbach. Here, the murder of little Lucia happened a year and a half ago - the crime is also attributed to the serial killer. However, village policeman Michael Martens (Wotan Wilke Möhring) does not believe in this explanation and wants to continue investigating, much to the chagrin of the residents. His wife Rosa (Ulrike Krumbiegel) is not thrilled that Michael wants to go to Berlin in the middle of harvest season and, moreover, leaves her alone with their two children Christian (Hauke Diekamp) and Sarah (Laura Alberta Szalski). The marriage is in crisis anyway: Michael has neglected his wife and children over his investigations into the Lucia case. His son has had massive problems at school since the murder and is behaving particularly conspicuously. When Michael meets Gabriel, the latter is initially extremely cooperative, to the surprise of the experts. He makes statements about the Lucia case and claims to know the murderer. The police then also like to see Michael as the ideal man to elicit Gabriel's terrible secrets. But Gabriel's mind games overwhelm the devout Christian and moral man Michael. He fails and is taken off the case. Only Seiler is willing to lead Michael, who by now seems fanatical, to Gabriel's apartment. There they actually find cleverly hidden evidence. The case seems to be solved and Michael exuberantly celebrates his investigative success. A few days later, however, it is discovered that the evidence does not clearly prove Gabriel Engel's perpetration. Lucia's murderer could therefore still be at large - and in all likelihood even turn out to be one of the villagers. As the search continues, Michael's life becomes completely unhinged. He can no longer distinguish between good and evil and becomes a danger to those closest to him. A race against time begins...