Bilson is born into a Hollywood family: father Danny is a writer-director-producer, grandfather Bruce is a director and her great-grandmother Hattie was a screenwriter. At 6, her father directs her in The Wrong Guys with comedians Louie Anderson and Richard Lewis.
After a one-year stint at San Diego's Grossmont College, Bilson begins auditioning for commercials and pilots. After a failed audition for an Everwood role, the aspiring actress is recommended to series creator Josh Schwartz who is casting for The O.C., a drama revolving around the lives of four teens living in California's well-heeled Newport Beach enclave.
The O.C. premieres, drawing comparisons to Beverly Hills, 90210 for its portrayal of SoCal's elite. Bilson plays Summer, a spoiled teen who lives the high life with BFF Marissa (Mischa Barton) and schoolmates Seth (Adam Brody) and Ryan (Benjamin McKenzie). She tells Cosmo that Summer was originally a bit part intended for a tall blonde, but she parlays it into a starring role.
While their The O.C. characters Summer and Seth bicker and flirt onscreen, Bilson and Brody begin their own romance. The two stars are soon spotted together everywhere from the Viper Room to walking their puppy, a pit bull terrier named Penny Lane.
Bilson films The Last Kiss, an adaptation of the original Italian hit, L'ultimo bacio. She stars as feisty undergrad Kim who woos Zach Braff. Director Tony Goldwyn has nothing but praise for Bilson, saying, "[She] is an incredibly sexy, beautiful young woman, but she also has so much intelligence, wit and substance to her."
Bilson begins filming Jumper, a sci-fi thriller starring Hayden Christensen and Samuel L. Jackson. A week later, despite reports that their relationship is on the rocks, Bilson and Brody are seen holding hands on location in Toronto, where Jumper is being filmed.
Though it looks as though Summer and Seth are a match made in TV heaven, Bilson calls it quits with Brody after more than three years together. "It was a typical romance and they just grew apart," a source tells PEOPLE. "They’ve been on and off for awhile now." In January, FOX announces its decision to cancel The O.C. after a steady decline in ratings.
Bilson and Christensen get engaged quietly over the holidays, a friend of the actress tells PEOPLE. "They're so excited," says the pal, adding that no wedding date has been set. "They're a great couple. Rachel seems thrilled beyond belief."
After rumors circulate for months that Bilson and Christensen are on a break, the actress's rep confirms that "their engagement is off." Now Bilson is "focusing on her career, spending time with her family and just moving forward," a friend tells PEOPLE. But a few months after ending their engagement, the pair begins "dating again," a Bilson pal tells PEOPLE.
Bilson makes plans to return to television in the CW's new series Hart of Dixie, in which she'll play Dr. Zoe Hart, a Manhattan medical school graduate who accepts an offer to join a small-town practice. "Everything felt right. You know when you just know," Bilson says of the show, which reunites the actress with former O.C. masterminds Josh Schwartz and Stephanie Savage.
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