Knife of Ice (1972) is an Italian horror movie that I recently watched on Shudder. The storyline follows a young lady who was in an accident as a child that she barely survived but killed her parents. She's mute post accident and moves with her uncle in the countryside of Spain. When her wild and sex craved cousin comes to visit they go out looking for boys only to encounter a serial killer that kills the cousin and begins hunting the mute young lady.
This movie is directed by Umberto Lenzi (Black Demons) and stars Carroll Baker (Giant), Alan Scott (Lola), Evelyn Stewart (The Leopard), Eduardo Fajardo (Django), George Rigaud (Horror Express) and José Marco (Horror Express).
This is a bit of an uneven movie that is a classic "who done it" with some unique elements. The kills are very average, the detective is an annoying "know it all" but the acting is very good. The music is classic 70s horror and fun. The creepy guy in the bushes was an entertaining character, the satanic worshipping was interesting and the twist ending is really good and worthwhile.
Overall, this is a slightly above average addition to the horror genre that I would score a 6.5/10 and recommend seeing once.