The movie opens up with young woman crying in a car in traffic. We then move to a childhood flashback and voiceover. The voice, and the images, are of Stacy (Brittney Murphy), whose father left her when they were young. She was raised by her mother, who taught her by example that if life gets rough, sing Carly Simon songs. We then see Stacy at her present job, as an assistant television producer, and she reveals her dream to be the next Diane Sawyer someday.
Stacy works on the "Kippie Kann" television show, which is a confrontation talk show very much like "The Jerry Springer Show." Kippie Kann is played by Kathy Bates, and Stacy is assisted by a member of the production staff, Barb (Holly Hunter). Promotions are made based upon who brings up the ideas that get turned into shows, and the person who comes up with the most ideas gets to produce their sweeps live show.
Ira at the show, a wild haired geek/nerd type, comes up with many ideas, but gets them stolen by other staff members, especially his ideas for shows using midgets. He comes up with an idea for a show about women who have caught their man cheating by looking through their palm pilot or electronic organizer - the modern equivalent of the "Little Black Book."
We then meet Stacy's boyfriend, Derek (Ron Livingston). Derek is a hockey sports scout, and is travelling out of town, and asks Stacy to watch his house, and take care of his dog, Bob. She voice overs that they've been dating for a while, but he is unable to commit. While he is packing, a supermodel appears on TV, and he comments that they used to date, but that they broke up. Sure enough, Derek leaves his Palm/Treo/Clie at home, and calls her and asks her to look up information on it. She figures out the password, "Bob", and also a discovers a box of ex girlfriend memorabilia, and snoops through both, finding photos and names of ex girlfriends. When Lulu calls and leaves a message on Derek's answering machine, Stacy smashes the answering machine in pieces. She mentions the ex girlfriends to Barb at the office, and Barb sets up meetings between her and his ex girlfriends, on the pretext that they are interviewing them for potential future shows.
First Lulu, the supermodel is brought in. The topic is quickly steered towards the subject of ex boyfriends, and she comments that she was with her last boyfriend, Derek, only for the sex, and that it was aggressive, wild, and that Derek never cheated, but that she broke up with him because she travelled and was insatiable.
She then finds out that one of Derek's ex girlfriends is a Doctor. Believing that she is a podiatrist, she schedules an appointment to discuss warts. She finds out at the examination that Dr. Keyes is a gynecologist, and author of "Keyes to your Vagina", as well as founder of a vitamin company. She sees pictures of Bob, the dog, and Dr. Keyes, that were just taken at a picnic weeks before, and suspects that Dr. Keyes is still seeing Bob and Derek.
She then meets a chef, Joyce, who she found through vacation pictures on the palm pilot in a thong with Derek's parents in a tropical location, after he told Stacy that he doesn't take women to meet his parents. They bond and become friends, and Joyce tells her that although she broke up with Derek because they were going different directions at the time, she always thought they'd end up together. They each bought boomerangs for each other to symbolize that fact. Joyce cries and reveals that she's framed hers in her house, and she thinks Derek probably thew his away. Stacy then lays on the floor and sings Carly Simon's song "Nobody Does it Better", facing the camera.
When Stacy goes back to meet Joyce again, Lulu appears with television cameras surrounding her, and Lulu and Joyce get into a big argument. Stacy offers to have Joyce on the TV show for a television cook off, where she can show her skills. Stacy worries about what will happen when Joyce finds out she lied, and that in fact she's dating Derek.
Stacy goes home and finds the boomerang on a bookshelf. She knows that Joyce, who is now her friend, cares deeply for Derek, and that Derek probably cares for her also. Stacy confronts Derek about all of this when he gets back from his trip, and he states that he took Joyce to meet his parents because she was "different".
The big day of the live show finally arrives, and Barb is chosen to be the producer. Her and Stacy get started without a minute to lose, and the show goes live. They then push Stacy through the trademark ringing door, and they reveal that she is an assistant producer, and that the TV show is not a cook off, but a chance for her to confront Derek's ex girlfriends. One by one, the ex girlfriends are brought on stage, and they tell their story. Then Derek is brought out, and after hearing all of this, wants nothing to do with the show. Joyce, almost in tears, tells how much she cares for him, and Stacy decides that they would be better off together. Stacy then walks off the show, and is fired.
We then flash back to the opening scene, of Stacy in her car crying. She is now without a job, so she is singing Carly Simon songs and going on job interviews. She finally gets a job working for Diane Sawyer, her dream job. Stacy is freaking out with excitement and calls her mom on the phone. She tells her mom she got the job. Carly Simon walks in and wishes Stacy good luck. Stacy faints. Stacy's mom on the other line is still connected and Carly picks up the phone speaks with her. The mom faints as well.
In a voice over Stacy says that life is getting better and she is glad that she isn't with a liar like Derek anymore.