Mischa Barton has confirmed her involvement in 'The Hills: New Beginnings'.

Mischa Barton's Instagram (c) video

Mischa Barton's Instagram (c) video

The 32-year-old actress - who is known for starring in teen drama series 'The O.C.', which ran from 2003 to 2007 - was rumoured earlier this week to be joining the cast of the reboot of the popular MTV reality series 'The Hills', which will air in 2019 and will be subtitled as 'The Hills: New Beginnings'.

And on Wednesday (03.10.18), the blonde beauty shared a video on her Instagram account which confirmed the news.

The short clip showed Mischa in her car, taking off a pair of sunglasses and saying "Welcome to The Hills b***h", whilst Natasha Bedingfield's 2004 hit 'Unwritten' played in the background.

She captioned the clip: "The secret's out... I'm joining the cast of The Hills. When MTV approached me with the chance to be a part of the reality show that was inspired by The OC, it felt like the perfect opportunity for an irresistibly inviting new chapter. (sic)"

Mischa was rumoured to be taking part in the series after sources said her beginnings on 'The O.C.' would make for "good TV".

An insider said: "She was around back in the day and went to all the clubs. She could make for good TV."

Mischa will be joining the likes of Heidi Montag, Spencer Pratt, Audrina Partridge, Stephanie Pratt, Whitney Port, and Brody Jenner on the rebooted show, after several of the returning cast took to social media to confirm their roles.

Brody - who is the son of Caitlyn Jenner, formerly known as Bruce Jenner - will appear on the show with his wife Kaitlynn Carter Jenner, and after rumours of their involvement surfaced in August, he took to Instagram in September to confirm his return.

Posting a picture of the Sunset Strip with his head shot adorning one of the buildings, the 35-year-old reality star wrote: "Don't call it a comeback. THE HILLS: New Beginings coming soon to @mtv #haterswillsayitsphotoshopped (sic)"

Stephanie, 32, previously took to Instagram to announce that she will also be returning, saying: "I am so excited to start filming #TheHills #NewBeginnings #MTV with my friends & family! it's going to be EPIC @mtvthehills."

Whilst Whitney confirmed her involvement when she wrote: "Throw back to my first VMAs look. Good thing I get to go back and make up for my insane looks on #thehills on the NEW HILLS REBOOT!!! Maybe they'll let me out of the fashion closet this time. #mtv. (sic)"