John Dullaghan provides the voice for Sam Dobbs during the sex scenes and in the scenes before he enters the pool. He also provides several of The Zodiac's voice-overs.
Sandy Dempsey acts as a body double in some of the underwater scenes. Her butterfly tattoo is briefly visible in two different shots.
The After Hours Cinema DVD displays John Holmes's name before the title is shown, although the film originally didn't have any credits.
Some of the music has been lifted from the incidental music of Edwin Astley used on The Saint TV series