Trivia: The Attorney General in the final scenes with the cowboy hat and round sunglasses is the stunt coordinator. The director gave him a small part to say thank you for his contribution to the film.
Trivia: Filming of this movie took only eighteen days.
Trivia: In the film poster, the "Not alone" on Halle Berry's forearm is written running from wrist to elbow. However, in the film, when she removes her bandages, it runs elbow to wrist.
Trivia: Near the end, the publisher tells Sarah Morton that he is disappointed in her latest book and asks her "Where's the plot twist?" Interestingly enough, the viewer is presented with a very big plot twist a short while later as the movie ends.
Trivia: The voices for the singing busts are provided by the Dapper Dans, a barbershop quartet that performs regularly at Disneyland park in Anaheim, California.
Trivia: The scene directly before the first victim, "the movie star", is killed she is talking to herself in the mirror. You can see her reflection and the reflection of the window behind her. If you pay close attention you can see that there is a silhouette in the curtains. Eventually the lightning flashes and you can see the face of the little boy in the silhouette looking into the window at her.
Trivia: Nicole Kidman was originally cast as Frannie, but Meg Ryan insisted on playing the role and also auditioned, something unusual for famous actresses like her.
Trivia: The second entry in the "Vengeance Trilogy" by director Park Chan-wook. The three films are not directly related, but are connected by similar visual styles and themes of revenge and retribution. The first film was "Sympathy for Mr. Vengeance," while the final film was "Lady Vengeance." All three films have been optioned for American remakes, although as of 2019, only "Oldboy" has been successfully remade.