A German serial killer preys on boys and young men during the so-called years of crisis between the wars. Based on the true story of Fritz Haarmann, aka the Butcher of Hanover and the Vampire of Hanover.
- Release Date: July 12, 1973
- Runtime: 82 minutes
- Production countries: Germany
- Original Title: Die Zärtlichkeit der Wölfe
- Original Language: Deutsch (German)
Actors: Margit Carstensen, Ingrid Caven, Kurt Raab, Jeff Roden, Wolfgang Schenck