Directed and written by Dario Argento.
A musician is stalked by an unknown killer who's blackmailing him for an accidential killing of another stalker.

Starring:
Michael Brandon
Mimsy Farmer
Jean-Pierre Marielle
Bud Spencer
Aldo Bufi Landi
Calisto Calisti
Marisa Fabbri

One DVD, from VHS.
£3.99