'John Lithgow''s debut.
Based on a novel of the same name by "Michael Douglas," later revealed to be a pseudonym for Michael Crichton and his brother Douglas.
In his memoir, Drama, Lithgow credits Brian De Palma with getting the actor his feature film debut. In the summer of 1966, between his junior and senior years of college, Lithgow had tried to launch his own theater production company in Princeton, New Jersey, called The Great Road Players. The effort was a financial and promotional disaster, but De Palma happened to come down to see friends from Columbia in the some of the shows, and found Lithgow terribly funny in some Moliere one-acts. Four or five years later, the director passed the actor's name to Paul Williams when the latter was searching for a "patrician Harvard undergraduate dope dealer" for his film. Williams had attended Harvard as well, and remembered having seen Lithgow on stage there, so he interviewed and hired him. Of course De Palma also later cast Lithgow as the villain in at least three of his later films, Obsession (1976), Blow Out (1981), and Raising Cain (1992).