Forced Entry (1973 film)

It stars Harry Reems (credited as Tim Long) as an unnamed and psychotic Vietnam War veteran who sexually assaults and kills women who stop at the filling station where he works as an attendant.

Called "one of the most disturbing and unpleasant porn features ever made," the film utilizes actual footage of the war, predominantly in the rape and murder sequences.

[1] After opening with newspaper articles, footage, and quotes relating to the Vietnam War and the psychological condition of the American soldiers who have returned from it, the authorities are shown investigating a crime scene in which a man was shot in the head.

Going back an unspecified amount of time, the man is revealed to be a gas station attendant, and is shown coercing a female customer into giving out her name and address by claiming they are needed for a credit card transaction.

When the husband leaves, the attendant breaks into the apartment and forces the woman to perform oral sex on him while he verbally abuses her, slitting her throat after he climaxes.