Fritz Haarmann, aka the 'Butcher of Hanover' and the 'Vampire of Hanover', was a German serial killer responsible for the murders of two dozen boys and young men during the so-called years of crisis between the wars. His case would partly inspire Fritz Lang's 'M', and its central character portrayed by Peter Lorre, as well as this forgotten gem from 1973. 'Tenderness of the Wolves' treats the viewer to a few weeks in the company of a killer. Baby-faced and shaven-headed, in a manner that recalls both 'M' and F.W. Murnau's 'Nosferatu', Haarmann is a fascinating, repulsive figure. Using his status as a police informant to procure his victims, he dismembers their bodies after death and sells the flesh to restaurants, dumping the remainder out of sight. This isn't an easy film to watch, but it certainly gets under the skin...Produced by Rainer Werner Fassbinder (who also supplies a shifty cameo), 'Tenderness of the Wolves' provided two of his regular actors with a means of expanding their careers. Ulli Lommel later responsible for the infamous video nasty 'The Boogeyman' made his directorial debut, while Kurt Raab wrote the screenplay as well as delivering an astonishing performance as Haarmann.