Im Abgrund plot
Child murderer Hagenow is released after 15 years in prison, although the police believe he is still a danger to society. Detective David Wallat is ordered to keep an eye on the man and, if possible, catch him in the act so that he ends up behind bars for good. Hagenow rents a room in the house of the idealistic village pastor Berkenbusch and lands a job in a local sawmill. He is observed around the clock, but when Wallat loses sight of him during a nighttime walk, Father Berkenbusch's son appears to have disappeared without a trace the next morning.