Zwei Finger einer Hand (1975)

Two gruesome child sex murders cause panic among the residents of the English industrial town of Blackburn. When a four-year-old girl is kidnapped from the hospital and found abused and murdered that same night, the authorities turn to Scotland Yard. The only clue to the killer are two fingerprints on a glass bottle. The London officials then initiate an unprecedented search operation: 35,000 houses are searched, the fingerprints of all male residents of the city are taken - without success.