"Psycho" is based on the 1959 novel of the same name by Robert Bloch which in turn is based loosely on the case of convicted Wisconsin murderer Ed Gein. Both Gein and "Psycho"s protagonist, Norman Bates, were solitary murderers in isolated rural locations. Both had deceased, domineering mothers, and had sealed off one room of their house as a shrine to their mother, and both dressed in women's clothing. However, there are many differences between Bates and Ed Gein. Among others, Gein would not be strictly considered a serial killer, having officially killed "only" two people. Peggy Robertson, Hitchcock's production assistant, read Anthony Boucher's positive review of the Bloch novel and decided to show the book to Hitchcock, even though readers at Hitchcock's home studio Paramount Pictures rejected its premise for a film. Hitchcock acquired rights to the novel for $9,500. He reportedly ordered Robertson to buy up copies to keep the novel's surprises for the film. Hitchcock chose to film "Psycho" to recover from two aborted projects with Paramount: "Flamingo Feather" and "No Bail for the Judge". Hitchcock also faced genre competitors whose works were critically compared to his own and so wanted to film new material. The director also disliked stars' salary demands and trusted only a few people to choose prospective material, including Robertson.