Rise to Fame
She auditioned for Marissa Cooper and didn't get it. The role that rewrote her trajectory was Summer Roberts, a character written for maybe three episodes. By the Tijuana episode, the writers realized they had something, and she became a series regular by Episode 7. Summer was supposed to be shallow banter to Seth Cohen's neurosis, but Bilson made her genuinely funny, and the Seth/Summer dynamic ended up carrying the show through four seasons. She came from a family four generations deep in Hollywood. Getting cast almost by accident was the part nobody planned.
In the Spotlight
After The O.C. wrapped, she spent years trying to escape Summer Roberts without quite managing it. Hart of Dixie gave her four seasons as a fish-out-of-water doctor on the CW, solid but not a career reset. Take Two got cancelled after one season in 2018. Rather than keep fighting the nostalgia, she leaned into it: a Welcome to the OC, Bitches! rewatch podcast, then a 2024 ad campaign for 21Seeds tequila where she reprised Summer Roberts in spots that played like she'd never left. The Scrubs revival and a Fox cooking drama (The Sharper Your Knife, the Less You Cry) suggest she knows Summer Roberts was always going to be the launchpad, not the destination.
Side Notes
Four generations of Hollywood on her father's side, and she still almost didn't make it in. Her great-grandfather ran the movie trailer department at RKO; her grandfather Bruce Bilson directed sitcoms for decades. She went to Notre Dame High School in Sherman Oaks alongside Rami Malek and Kirsten Dunst, none of whom ended up in the same corner of entertainment. Reportedly at 13, a head-on collision left her unconscious for a few days; she learned piano during recovery for hand-eye coordination. Her credit as Wonder Woman's voice in an animated Justice League film is the kind of thing that gets buried under Summer Roberts jokes.