This early 70's giallo by Umberto Lenzi is certainly among the best in his filmography and also in the whole genre. Personally I think Lenzi's best films are the funny cartoon-turned-film Kriminal, the stylish giallo Seven Blood-Stained Orchids, the explosive Napoli violenta and this. In the eighties he did plenty of film trash in form of Eaten Alive, Hitcher in the Dark or Black Demons, all of which are ripping something off and/or very dull and slow moving. Knife of Ice came when the giallo boom was at its hottest and the result is convincing.
　　Technically the film is superb, containing great cinematography in the beginning when we learn about the main character's trauma towards trains. From this point on, Lenzi shows us his ability to benefit the widescreen and, for example, the bicycle ride near the forest is genuinely beautiful! This scene also shows Lenzi's ability to build suspense, very slowly but meaningfully. After all, there aren't so many murders in the whole film, only the suspense circulating around the murderer's identity.
　　One suspect is a devil worshipper which brings new aspects to the mystery. Since the final scene takes place in a church, one can wonder if Lenzi wanted to comment on something, maybe the hypocritical morale of church and superstition. The main character (Carrol Baker) is mute which demands a lot from her face and eyes. The actress works very well, giving us a believable performance circulating around the emotions of fear and mental pain. The other actors are good, too. The finally, however, may not give too positive a sight about female sex since they all are expressed rather negatively in the film, one way or another. Still this is easily among the most noteworthy in the genre, not as bloody as the Argento films, for example, but equally suspenseful and visually also interesting.

　　居住在德里，以卖枪为生的社会青年索努.迪力一向得意于自己坑蒙拐骗的本领，然而突如其来的恋爱却唤起了他回归正道的念头。在他想要退出江湖时，一位质朴的警察来了，在他的威胁之下，索努被迫作为警方线人深入德里枪支贸易的最深处，从黑暗走向更深的黑暗……他能否全身而退？他的爱情会被谎言所断送吗？警方看似正义的行动背后有什么秘密？这次卧底之行从他的身上带走的，会是良知，爱情，羁绊，还是生命？

　　到东京发展模特儿事业的明日香，在友人葵的介绍下到香纯的家居住。香纯过去也当过模特儿，但随着她身边的人一一死去，香纯是「恶魔」之说不迳而走。与此同时，在她们住所对面的酒店发生恐怖杀人事件。受害者不但活生生被支解，尸体更被看成艺术品般加上装饰，并有凶手留下黑色的唇印。然而，这一切只是明日香和香纯恶梦的开始……