'O.C.' Nostalgia Alert: Mischa Barton Joins 'The Hills' Reboot
The Hills -- Then and Now

"The Hills: New Beginnings" premieres in 2019. No action is needed.

Alert! Alert! This is not a test. Mischa Barton has joined "The Hills" reboot.

Yes, the star of "The O.C." -- the Fox teen drama that inspired MTV to create "Laguna Beach," which led to "The Hills" -- will be mixing and mingling with MTV reality stars Audrina Patridge, Brody Jenner, Heidi Pratt, Whitney Port, Spencer Pratt, Stephanie Pratt, Frankie Delgado, Jason Wahler, Justin "Bobby" Brescia on "The Hills: New Beginnings."

The reality series, which is currently in production, will follow the returning fan favorites, their children and friends while they navigate their personal and professional lives.

Barton is best known for playing Marissa on "The O.C." before her character was killed off in 2007. She has acted in smaller roles in the last few years and most recently made headlines back in March when she denied crashing a U-Haul into a building. This will be her reality show debut.

After hearing the news, Spencer tweeted that he would be binge-watching "The O.C."

O.G. "Hills" stars Lauren Conrad and Kristin Cavallari will not be returning for the reboot.

MTV confirmed the reboot at the 2018 Video Music Awards in August when some of the members hit the red carpet together. The network released a 30-second teaser the night of the awards show. Check out the trailer below.

"The Hills: New Beginnings" is slated to premiere in 2019.

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