Sophia Bush joins 'Grey’s Anatomy' season 21: See the fun video announcement

Sophia Bush is joining the season 21 cast of " Grey's Anatomy ."

In a video that she shared on Instagram on Tuesday about the exciting news, the " One Tree Hill " star, who has previously portrayed a doctor in the show "Good Sam," wears a set of the iconic blue scrubs.

"I just wasn't done with my scrubs 💙," she captioned the post.

Bush will play the recurring role of Dr. Cass Beckman, a trauma surgeon at Seattle Presbyterian whose husband is David Beckman, a cardiothoracic surgeon at Grey Sloan Memorial.

According to information about her character, Beckman is described as "amiable, fun and a little messy around the edges."

Season 21, which kicked off last month on ABC, picked up in the aftermath of the season 20 finale, which saw Meredith (Ellen Pompeo) at odds with Catherine Fox (Debbie Allen).

Bush will make her "Grey's Anatomy" debut on the show in the episode airing on Nov. 7.