Sophia Bush Officially Scrubs In For 'Grey's Anatomy' Season 21

​Who's in the Grey's Anatomy season 21 cast?

Deadlinereports that One Tree Hill star Sophia Bush will join the series starting November 7 as Dr. Cass Beckman, "an amiable, fun, and a little messy around the edges trauma surgeon." Her husband, David Beckman, is a cardiothoracic surgeon at Grey Sloan Memorial Hospital. "I just wasn’t done with my scrubs," Bush, who produced and starred in CBS' medical drama Good Sam, says on Instagram.

The rest of the Grey's Anatomy cast for season 21 includes Ellen Pompeo, Chandra Wilson, James Pickens Jr., Kevin McKidd, Caterina Scorsone, Camilla Luddington, Jason George, Kim Raver, Jake Borelli, Chris Carmack, Anthony Hill, Alexis Floyd, Harry Shum Jr., Adelaide Kane, Midori Francis, and Niko Terho.

​How can I watch season 21 of Grey's Anatomy?

New episodes of Grey's Anatomy season 21 premiere on ABC every Thursday at 10 PM EST/9 PM CST. They're also available to stream on Hulu.

​Is Grey's Anatomy season 21 out?

Yes, Grey's Anatomy season 21 premiered on September 26 on ABC. Catch up on the first three episodes before episode 4 comes out on October 17!

​How many episodes are there?

Grey's Anatomy season 21 will have 18 episodes, meaning we'll get a new episode every week until the finale next year. Check back here for the full list of episodes!

• "If Walls Could Talk"
• "Take Me to Church"
• "I Can See Clearly Now"
• "This One's for the Girls"
• "You Make My Heart Explode"

​Is Ellen Pompeo in season 21?

Yes, Ellen Pompeo has returned for Grey's Anatomy season 21! The season opens with Meredith Grey and Catherine Fox disagreeing over their Alzheimer’s research.