Trivia: The big speech from "Couldn't you find anyone worse? A child molester..." to the bit where Stu is shot was filmed in one take. Colin Farrel did everything and surprised himself and the crew. When he hit the floor, the crew (and the extras) had to contain their applause until the cameras stopped rolling.
Trivia: The phone that Colin Farrell (Stu) was hooked up to actually had a person talking to him, to keep him sane during the confining shoot.
Trivia: This movie took only 12 days to shoot. The scenes inside the phone booth were shot in 10 days and the exterior shots were taken over the other 2 days.
Trivia: The large ad behind Stu and the phone booth reads, "Who do you think you are?" A fitting question for Stu, who has an abrasive personality before he enters the phone booth. (00:09:05)
Trivia: Ron Eldard was originally cast as The Caller and even shot all of his scenes and dialogue for the film but director Joel Schumacher felt he didn't sound intimidating and frightening enough so he re-shot with Kiefer Sutherland in the role instead.
Trivia: When The Caller tells Stu that "you can be shot 41 times for just pulling out your wallet," he is referring to Amadou Diallo, an innocent West African immigrant who was shot to death in his apartment room in 1999 when undercover New York City police detectives fired 41 shots at him after he pulled out his wallet. They thought he was pulling out a gun. Before the time of the shooting, Diallo, was suspected to be a serial rapist which he was not. (00:32:25)
Trivia: The extras had no idea what was going to happen each day (the film was shot in sequence) so their reactions are totally real.
Trivia: Jim Carrey was originally cast in the lead the role as Stu but dropped out due to other commitments. Will Smith was considered to take over the part but director Joel Schumacher opted for Colin Farrell instead.
Answer: The pizza man is intended by the Caller to be a decoy so he can get away. The Caller sends the pizza man to the phone booth so that Stu will identify him later in the apartment, giving the police a convenient answer to the mystery while the real Caller escapes. In fact, at the end of the movie, the Caller comes to visit Stu - obviously he's not the dead pizza delivery man.
Phoenix