‘Grey’s Anatomy’: All the Famous Guest Stars You Forgot About

Over the past 15 seasons, many famous faces have visited Grey Sloan Memorial Hospital – some of them even appeared when it was called Seattle Grace Mercy West Hospital!

While multiple stars appeared on Grey’s Anatomy for long stretches, others had one-episode stints. During season 6, Demi Lovato – who had already dropped two albums at the time – played a woman incorrectly diagnosed with paranoid schizophrenia. During season 11 (oddly enough), Millie Bobby Brown played Ruby, a girl who saves her mother’s life by calling the hospital when her mom gets hurt, prompting the doctors to walk her through what to do.

Demi Lovato and Millie Bobby Brown on Grey's Anatomy
Demi Lovato and Millie Bobby Brown on Grey’s Anatomy Mitch Haddad/ABC via Getty Images; Frederick M. Brown/Getty Images

Before crushing skulls on The Walking Dead, Jeffrey Dean Morgan crushed hearts as Denny; he first appeared in season 2 and ended up starring in 23 episodes as Izzy’s (Katherine Heigl) love interest. He recurred through season 3 and his last appearance was in season 5. Four seasons later, his wife Hilarie Burton appeared on the show, playing Dr. Lauren Boswell. She even had a quick fling with Arizona (Jessica Capshaw) during her four-episode arc.

Watch the video above to find out who else has appeared on the medical drama.

Grey’s Anatomy airs on ABC Thursdays at 8 p.m. ET.

Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!

Want stories like these delivered straight to your phone? Download the Us Weekly iPhone app now!

Close popup

Welcome to In Motion

Bring photos to life with Us Weekly's exciting new mobile experience!

What's In Motion? Tell me more

What's In Motion?

Go back

How to Use In Motion

What's In Motion? Tell me more