Actors playing shot policemen, who had to lie on the floor in pools of blood for long periods of time, to relieve the boredom, would sing and whistle the Monty Python song "Always Look on the Bright Side of Life", which had been at the time recently popularized in the movie Life of Brian (1979).
Lead actor Jack Thompson spent a considerable amount of time alone during principal photography, particularly between takes, where he would walk off to be by himself. This was part of his actor's process as the role he was playing was a character who was a loner who lived in semi-self-imposed isolation with his wife.
The film was shot in the Kokatahi-Kowhitirangi Valley, where Stanley Graham and his family did actually live and where all the events occurred (shootings, manhunt). There is a memorial to the victims of Stan Graham at the location of his house which has been demolished.
The green 1930 model A Ford used in the movie has a 1928/29 left side front fender, which can be seen as the truck stops in the driveway toward the end. The truck still has the wrong left front fender to this day.
The film was made and released about three years after its source non-fiction book "Manhunt: The Story of Stanley Graham" by Howard Willis had been first published in 1979. Then in 1981, Willis published "Bad Blood: The Story of Stanley Graham".