With a show as long as Grey's Anatomy (14 seasons and counting), there's bound to be plenty of famous cameos coming at you left and right. Some of these actors have gone on to make names for themselves after their appearance, along with some who were already well known at the time.
Here are 12 actors you definitely forgot were in Grey's!
12. Keke Palmer
The now Scream Queens star made an appearance on Grey's in Season 10, episode 16. She played a pregnant teen with a heart condition.
11. Abigail Breslin
You know her for her many roles growing up as a child star, who was featured on Grey's in Season 3, episode three. She played a character who suffered from a genetic condition that didn't allow her body to feel pain.
10. Vanessa Marano
The Switched at Birth alum played Holly on Grey's, a girl who was kidnapped and found in a ravine. This was in Season 8, episode 20.
9. Seth Green
This experienced actor had a two-episode spot on Grey's back in Season 4, episodes nine and 10. He played Nick, who had a tumor removed from his neck, only to die from a bursted artery.
8. Liza Weil
The Gilmore Girls alum played Izzie's friend who was going under chemotherapy. Although initially she responds to it, she ends up passing away. This was in Season 5, episode 23.
7. Christina Ricci
The Lizzie Borden Chronicles star (not to mention Casper and The Addams Family back in the '90s), was featured in Grey's back in Season 2, episodes 16 and 17. She played the girl whose hand was stuck on a live bomb inside a person.
6. Faye Dunaway
The legendary actress appeared on Grey's as Dr. Margaret Campbell, a doctor who Cristina does not get along with. This was back in Season 5, episode 16.
5. Dylan Minnette
We know him now as the star of 13 Reasons Why, but back in the day, Dylan Minnette made an appearance on Grey's. He played a little boy who was born without ears, in Season 4, episode five.
4. Neve Campbell
One of the original scream queens, Neve Campbell, played Derek's sister, Lizzie, who donates a nerve to him after his hand is injured in the plane crash. She's featured in Season 9, episodes eight and nine.
3. Mandy Moore
The This is Us star is clearly no stranger to tearjerker TV shows. In Grey's, she had a four-episode spot between seasons six and seven. She played Mary Portman, the woman who got an operation the day of Gary Clark's shooting and is taken off of life support after a procedure months later.
2. Sarah Paulson
The American Horror Story actress appeared on Grey's in Season 6, episode 15. She played Ellis Grey (Meredith's mom) in a flashback from 1982.
1. Demi Lovato
The successful singer appeared in Grey's back in Season 6, episode 22. She played Alex, a girl who discovered a small hole in her ear which caused her to self harm.