Gray’s Anatomy has been on the air for greater than 20 years, so it is sensible that quite a lot of massive Hollywood names have popped up for visitor slots over the past 22 seasons.
Established actors like Christina Ricci and Sarah Paulson have graced the halls of Seattle Grace hospital, in addition to some younger actors who went on to have massive careers: Millie Bobby Brown and Abigail Breslin, to call just a few.