In 1966, when Pinner was 26, he had just written the vampire comedy
Fanghorn, and was playing the lead role of Sergeant Trotter in
Agatha Christie's
The Mousetrap in the
West End of London. He decided to write a film treatment that dealt with the occult (like
Fanghorn) but which was also a detective story (like
The Mousetrap). Film director
Michael Winner liked Pinner's
Ritual treatment, and considered making it his next film, with English actor
John Hurt in mind for the lead role. However, Winner deemed the treatment to be "too full of imagery", and Pinner's agent, Jonathan Clowes, felt that Winner might sit on the project for a long time. The collaboration came to a halt. Clowes suggested that Pinner instead expand
Ritual into a novel, promising that he would get it published. Pinner wrote it in seven weeks, while he was still acting in
The Mousetrap. He would write sections of the novel on the tube train on his way into the West End, and even on his dressing room floor. While driving to his agent's office with the only completed copy of
Ritual in existence, Pinner accidentally left the manuscript on the roof of the car; it would most likely have fallen off and been lost forever if another driver had not alerted Pinner to his mistake. ==Reception==