The character of Michael Myers was named after the European distributor of Carpenter’s previous film, Assault on Precinct 13 as a kind of weird “thank you” for the film’s overseas success.
The original script, titled “The Babysitter Murders”, had the events take place over the space of several days. It was a budgetary decision to change the script to have everything happen on the same day (doing this reduced the number of costume changes and locations required) and it was decided that Halloween, the scariest night of the year, was the perfect night for this to happen.
Carpenter considered the hiring of Jamie Lee Curtis as the ultimate tribute to Alfred Hitchcock who had given her mother, Janet Leigh, legendary status in Psycho.
Dr. Sam Loomis is Michael Myers’ psychiatrist. Sam Loomis is also the name of Janet Leigh’s secret lover in Psycho.