As a way to get people to see the movie, the filmmakers made a print ad and cautionary trailer that read: 'During the last eight minutes of this picture the theatre will be darkened to the legal limit, to heighten the terror of the breathtaking climax which takes place in nearly total darkness on the screen. If there are sections where smoking is permitted, those patrons are respectfully requested not to jar the effect by lighting up during this sequence. And of course, no one will be seated at this time.' It worked and the film became a huge success because of it.
The role that eventually went to Alan Arkin was difficult to cast because the producers couldn't find actors willing to be cast in such a villainous role - not only terrorizing a blind woman, but terrorizing beloved Audrey Hepburn to boot! Alan Arkin later went on to say how easy it was for him to get the role because of the reluctance of other actors to take it.
During World War II, 16-year-old Audrey Hepburn was a volunteer nurse in a Dutch hospital. During the battle of Arnhem, Hepburn's hospital received many wounded Allied soldiers. One of the injured soldiers young Audrey helped nurse back to health was a young British paratrooper - and future director - named Terence Young who more than 20 years later directed Hepburn in Wait Until Dark (1967).
Audrey Hepburn and director Terence Young visited a school for the blind to learn more about the visually impaired. Hepburn learned enough Braille to appear to be reading and writing it, although she really isn't, a fact which wasn't apparent to audiences until home video, with rewind and freeze frames. Susy's use of Braille is a change from the Broadway script, where she uses things like sugar cubes to keep track of phone numbers. Writing phone numbers in Braille is a better real-world choice, and realistic touch, that developed from Hepburn's meeting with blind people.
Although she later admitted that she didn't intend to do so, Audrey Hepburn retired from films after this role, turning down all parts offered to her in order to devote time to raising her children. She would eventually return to the screen several more times, beginning with Robin and Marian (1976).
"Wait Until Dark" originated as a play by Frederick Knott (who also wrote "Dial M For Murder"). The play opened at the Ethel Barrymore Theater in New York City on February 2, 1966 and ran for 374 performances. Lee Remick starred as Susy Hendrix and was nominated for a Tony Award for Best Actress in a Play. Robert Duvall, Mitch Ryan and Julie Herrod were also in the cast. The play was directed by Arthur Penn.
A revival of the play, directed by Leonard Foglia, opened on April 5, 1998 at the Brooks Atkinson Theatre, where it ran for 97 performances. The cast included Marisa Tomei, Quentin Tarantino, and Stephen Lang.
During an interview for the DVD of the film, Alan Arkin claimed that he was once attending a viewing of the film when he heard what he called "a scream from like a thousand people, which scared the hell of me." When he asked what it was, the interviewer replied, "it's you!" Also, Arkin mentioned that this went on at screenings of the film for months, and at the climatic moment of the film, everyone went "berserk!"
The location of Susy's apartment is listed in IMDb as 4 St. Luke's Place in Manhattan (New York, NY). These days the street is called Leroy Street (between 7th Avenue S. and Hudson). The park seen across the street from the apartment is Hudson Park.