The film was shot at an old asylum near Uxbridge.
The plot of this movie revolves around mysterious events in the life of a man called "Andrew Marr". The real-life Andrew Marr, now famous as a journalist and television presenter in the U.K., was only in his early teens when this movie was made. The use of his name is purely coincidental.
Italian censorship visa # 65585 delivered on December 3, 1974.