Poliziotto senza paura (1978)

Private investigator Walter Spada is hired to find the daughter of a wealthy Austrian banker, who has been kidnapped by unknown assailants and whose trail has gone cold in Rome. His investigation takes him from the Italian capital to Vienna, where he uncovers a trafficking ring involving minors linked to prostitution. Although his investigation succeeds, the story ends with the deaths of the banker’s daughter, the banker himself—who kills himself with a cyanide pill—and the gang responsible for the kidnapping, led by a stripper who had intended to use the girl’s abduction to blackmail the banker.