Trivia

When released in America, the film was edited down for time, and the voices of the entire cast were dubbed by other actors (with the exception of Susan Penhaligon as her contract included a dubbing clause, allowing her to loop her lines with an American accent). This angered Robert Helpmann so much that he attempted to take legal action against the US distributors.

According to director Richard Franklin, the original cut of the film was 140 minutes long. Franklin says the footage cut for the 112 minute version no longer exists.

Special eye drops were used on Robert Thompson so he could hold his eyes open for up to a minute without blinking.

For the Italian release Brian May's score was replaced by music by Italian rock-band Goblin.

Actress Susan Penhaligon once said of this film project: "I liked the script so much that I thought - I want to go and do this film. I also felt that the Australian industry was taking off, and I thought it would be a good place to come and work. And I was proved absolutely right by my experience".

Everett De Roche: The film's writer as a S.E.C. Worker.