Right before shooting was set to begin, Pat Hingle suffered devastating injuries when he accidentally fell 54 feet down an elevator shaft in his apartment building. It would take Hingle over a year to fully recover from the accident. In the meantime, however, he decided to go ahead and do the film - he would simply incorporate his limp into the character. "I broke everything," Hingle said later. "I landed upright, so I broke hips and knees and ankles and ribs, and that sort of thing. That lurching walk that Ace Stamper has - that was as good as I could walk."
Even though they were supposed to be playing teenagers, Natalie Wood and Warren Beatty were approximately 22 and 23, respectively, at the time of filming. As a result, Elia Kazan decided that the other actors who were to play teenagers in the film should be in their early to mid-twenties as a way to make it easier for the audience to accept Wood and Beatty as teenagers.
Elia Kazan did whatever was necessary in order to bring out the best possible performances by his actors - it was one of the reasons he was known as one of the best directors in the business. From the beginning, he wanted to strip away the Hollywood glamour from Natalie Wood and get her to a more natural state for the camera, which was appropriate for the character of Deanie. It meant that Wood had to do without the sophisticated makeup and costumes she was used to, which caused her some anxiety. According her friend Mart Crowley, she was always trying to sneak on a little extra rouge or lipstick when Kazan wasn't looking.
To get Natalie Wood in the right frame of mind for the bathtub scene before they shot, Elia Kazan told Audrey Christie, who played her mom, to ask Wood a question that her real-life mother Maria Gurdin would ask her that would set her off.
The nightclub owner played by Phyllis Diller is Texas Guinan, a who owned the "300 Club", a New York nightclub in the 1920s. "Hello, suckers!" was her standard nightly greeting to her nightclub patrons.