Reporter Rowena Price (Berry) meets her childhood friend, Grace Clayton, who seeks her help in taking down Harrison Hill (Willis), a wealthy advertising executive. Grace gives Rowena her e-mails as proof of their extramarital affair, which Hill recently ended.
A few days later, Grace is found dead, drowned and poisoned with belladonna, and it is also found out Grace was in her first trimester of pregnancy, leading Rowena to suspect Harrison. With the help of researcher Miles Haley, Rowena goes undercover as a temp at his company, and enters into a game of cat-and-mouse.
This film contains examples of:
- The Bad Guy Wins: Maybe.
- Frame-Up: The Twist Ending reveals that Rowena's intention to follow Hill was to frame him for Grace's murder, presumably because there was much evidence pointing to him and she wanted to do it all for a feasible story.
- Karma Houdini: Rowena turns out to have murdered at least three people and successfully framed one of the murders on an innocent man, apparently getting away with it all in the end. However, someone may have witnessed her commit the murder.
- Parental Incest: In her childhood, Rowena was sexually abused by her father, prompting her mother to kill him.
- The Killer in Me: Rowena murdered her 'friend' (who was blackmailing her) and successfully pins the blame on the innocent, if slimy-looking businessman, Harrison Hill. Oh, and she murders again when another friend tries to blackmail her about setting up Hill. This one is pretty much the result of last-minute change on the ending to decide the identity of the killer.
- Stalker Shrine: It turns out that Miles actually made one of Rowena that's hidden in a secret room in his house.
- Stalker with a Crush: Miles. He sneaks into Rowena's house and watches her make out with her boyfriend, tries to flirt with her in instant messaging by posing as someone else, and has a freaky shrine dedicated to her in his house. Averted with Rowena, while she's using her romantic charm to get to him, it turns out she was doing it to frame him for Grace's murder.
- Too Dumb to Live: Miles finds out that Rowena, the reporter who was investigating her friend's murder, actually killed her after years of blackmail by the victim. After confronting her, he decides to blackmail the woman who just killed the last person who tried to blackmail her.
- Undercover When Alone: When Rowena is snooping around Hill's apartment looking for evidence of who the killer is and she finds evidence that seems to indicate that it's indeed Hill, she becomes visibly scared, even though it's revealed at the end that she was the killer all along. Apparently this is because the ending was changed to make her character the killer, all logic be damned.