The 1987 '18' rated UK video on the CIC label was the original cinema version. The later '15' rated release by Universal on the 4-Front label is the heavily edited US TV version. The 2008 Fremantle DVD features the original unedited version.
The theatrical version (the version released on video in the US) has scenes that were removed or severely truncated for broadcast on American TV, due to nudity, sex, the use of real life dwarfs, mutilated and otherwise deformed people, and allegedly profane references to the Catholic Church. Among the scenes reduced or removed for broadcast were Alison's first suicide attempt, her first encounter with her father's zombie, and her tea with her lesbian neighbors. A few scenes that were added for the TV version include a brief scene after the climax which shows detectives Gatz and Rizzo arriving at the brownstone house the morning after and seeing Father Hallin being being carried out by paramedics on a stretcher and being informed that he died of a heart attack.
The original opening of the film, including some outdoors shots filmed in northern Italy, implied that the sentinels were controlled by an order of the Catholic Church. These scenes were replaced in the American broadcast version with new scenes involving the same cast, now describing the sentinels as minions of an excommunicated order of defrocked priests, the "Brotherhood of the Protectors." In the TV version, Jose Ferrer's character is a monsignor instead of a cardinal, and has more dialog.
In the theatrical version, there is no voiceover in the final scene while the camera orbits the new Sentinel. The effect of seeing Alison transformed is startling, unsettling, and frightening. For the TV version, a voiceover has been added which diminishes this effect by implying that Alison is much happier in her new life than she was before.