Annette Hargrove is a heroine from the 1999 film, Cruel Intentions.
She was portrayed by Reese Witherspoon.
Kathryn Merteuil, the image of social perfection, takes the sheltered and naïve Cecile Caldwell under her wing, promising to turn Cecile into a model student like herself. Kathryn's real intention, however, is to take revenge on Court Reynolds, her ex-lover, who dumped her for Cecile. She intends to corrupt Cecile by getting her to sleep with as many men as possible, thereby destroying her reputation and teaching Court a lesson.
She asks for the help of her womanizing step-brother, Sebastian Valmont. Though Kathryn and Sebastian have collaborated in schemes of manipulation before, he initially refuses. He is busy planning another "conquest", the beautiful Annette Hargrove, a girl who has published a manifesto saying that she plans to keep her virginity intact until she is in love.
Kathryn does not think Sebastian has a chance with Annette, so they make a wager. If Kathryn wins, she gets Sebastian's vintage Jaguar, a 1956 XK140 Roadster; if Sebastian wins, she offers him a night of passion with her, as Kathryn knows she is the only girl Sebastian cannot bed. Sebastian initially rejects this deal, being very enamored of his car, but relents when Kathryn ups the ante, telling him that he can "put it anywhere."
Ronald Clifford, Cecile's music teacher for the summer, is also smitten with Cecile, and Kathryn makes arrangements for Ronald and Cecile to spend time together, hoping that he will take Cecile's virginity.
Sebastian, meanwhile, has a hard time seducing Annette. Though they have chemistry, she sees right through him and rejects his advances. Sebastian learns that Annette has been forewarned of his libertine ways by none other than Cecile's mother, Mrs. Caldwell. Wanting revenge, he joins Kathryn in her plans to corrupt Cecile.
Kathryn engineers Ronald's break-up with Cecile by informing Mrs. Caldwell of their flirtations; Mrs. Caldwell quickly ends their affair. Sebastian, in turn, calls Cecile to his house, ostensibly to give her a letter from Ronald. Once at his house, Sebastian blackmails Cecile and performs oral sex on her. The next day, Cecile confides in Kathryn, who advises her to learn the art of sex from Sebastian so that she can make Ronald happy in bed.
Meanwhile, Sebastian genuinely begins to fall in love with Annette, who returns his feelings but still keeps her defenses up. Sebastian declares that Annette is a hypocrite, waiting for love but refusing to sleep with the guy that loves her. Confused and beaten by Sebastian's logic, Annette relents - but Sebastian, now feeling guilty, refuses her. Heartbroken and embarrassed, Annette flees his aunt's estate. Sebastian tracks her down and professes his love, and they consummate their feelings.
Kathryn offers herself to Sebastian the next day, since he has won the bet, but he refuses; his romantic focus is now on Annette. Swayed by Kathryn's threat to ruin Annette's reputation, Sebastian coldly breaks up with Annette and returns to Kathryn. Kathryn, however, now refuses to sleep with him. After Sebastian tells Kathryn that he has arranged for Cecile and Ronald to be together, Kathryn reveals that she has known all along that he was truly in love with Annette, yet she manipulated him to give it up. While Sebastian may have initially won the bet, she made him lose his first true love, and she (Kathryn) does not sleep with "losers."
Sebastian realizes his mistake. After trying unsuccessfully to talk to Annette, he sends her his journal, in which he has detailed all his previous "conquests" but written his true feelings for Annette, hoping she will learn the truth for herself and forgive him.
Kathryn, meanwhile, informs Ronald of Sebastian's affair with Cecile; Kathryn also claims that Sebastian had hit her (in a deleted scene Sebastian does hit her). A furious Ronald confronts Sebastian in the middle of the street and a fight ensues. Annette, in search of Sebastian, comes upon the fight and tries to stop it. She is thrown into the way of an oncoming cab. Sebastian pushes her to safety and is hit by the speeding cab himself. Annette rushes to his side. Before he dies, he professes his love for her, and she reciprocates.
The new school year is inaugurated with Sebastian's funeral. During the service, Kathryn gives a self-important speech to the school about how she had unsuccessfully tried to get Sebastian to mend his ways and become a model student like herself. Halfway through her speech, students start walking out. Flustered, Kathryn rushes outside the chapel, where Cecile is distributing copies of Sebastian's journal (entitled "Cruel Intentions") to all the students. The journal shows all of Sebastian's inner thoughts: his conquests, his description of the bet, and a page on Kathryn, which finally exposes her manipulative and deceitful ways, including the fact that she hides a vial of cocaine in a crucifix she wears in the rosary beads around her wrist. The headmaster takes Kathryn's crucifix and opens it, spilling the cocaine. Kathryn's spotless reputation is destroyed, and people finally see her for the troubled, callous mastermind that she is.
In the final shot, Annette drives away in Sebastian's Jaguar, putting his sunglasses on, with his journal by her side and fond memories of being with Sebastian playing through her head.