Rachel Bilson has channeled her OC character, Summer Roberts, in a pink cutout dress.

The actress looked ageless as she attended an anniversary party for the show on Friday.

Rachel, 42, stood next to The OC’s creators – Josh Schwartz and Stephanie Carol Savage.

They all held drinks as they posed in front of a backdrop that had The OC and 21 Seeds on it.

“#ad When the OC calls… you answer!” Rachel captioned her Instagram post.

“Such a blast walking down memory lane the other night at The OC x @21seeds event.”

“I can’t believe it’s been 21 years since this show aired… Summer Roberts deserves a cocktail,” she went on.

Rachel is the ambassador for 21 Seeds, which is an infused Blanco Tequilla.

THE OC REUNION

Rachel wore a pink sleeveless dress, with cutouts on her hips.

A pink flower sat in the middle of the outfit, which came above her knees.

The actress added a pink Valentino purse on her shoulder and pink chunky high heels on her feet.

In the second photo, Rachel, Josh, and Stephanie, all posed with the band, Phantom Planet.

Phantom Planet sang the theme song for The OC called California.

Rachel also snapped photos with stylist Johnny Wujek and her friend, Lea Grace Griffin.

On her Instagram Stories, she shared that she “had a blast celebrating The OC’s 21st birthday!” and loved getting the “OGs back together again.”

ABOUT THE OC

The OC aired on Fox for four seasons from 2003 to 2007.

I can’t believe it’s been 21 years since this show aired… Summer Roberts deserves a cocktail

Rachel Bilson

The drama followed the intertwined lives of the Cohen, Cooper, and Nichol families.

Ryan, a teenager who found himself on the wrong side of the tracks, finds himself in well-to-do Newport Beach.

He is taken in by a lawyer and his family and winds up in the middle of wealthy high schoolers and their snarky attitudes and angst.

The OC stared Peter Gallagher as Sandy Cohen, Kelly Rowan as Kristen Cohen, Ben Mackenzie as Ryan Atwood, Mischa Barton as Marissa Cooper, Adam Brody as Seth Cohen, Chris Carmack as Luke Ward, Tate Donavan as Jimmy Cooper, Melinda Clark as Julie Cooper, Rachel Bilson as Summer Roberts, Alan Dale as Caleb Nichol, Autumn Reeser as Taylor Townsend, and Willa Holland as Kaitlin Cooper.

Summer is a popular socialite, who is Marissa’s best friend and Seth’s crush.

She was only supposed to appear in a few episodes, but became a fan-favorite and wound up becoming a regular for the rest of the series.

Summer is an animal activist and was more intelligent than everyone thought, getting accepted to Brown University.