This film finished production in 1999, and its original release date coincided with the Columbine High School shootings. The release was postponed because of the film's themes of violence and murder in a high-school setting.
The studios were initially hesitant about giving the film a one-letter title. The original title was "Odin". But they eventually decided the one-letter title was better because it was unique. The "O" also resembles a basketball hoop, which Mekhi Phifer appears to be holding on the poster.
The music at the end of the movie, "Ave Maria", is from the end of Giuseppe Verdi's opera "Otello", which was also based on the William Shakespeare play "Othello".
Both Julia Stiles and Andrew Keegan appeared in a previous high-school adaptation of a William Shakespeare play - 10 Things I Hate About You (1999).
Third modern William Shakespeare adaptation with Julia Stiles. The others being 10 Things I Hate About You (1999) and Hamlet (2000).