From left: Ellen Pompeo, Kelly McCreary, James Pickens Jr., Linda Klein, Caterina Scorsone and Giacomo Gianniotti on the set of ‘Grey’s Anatomy,’ posted on Instagram on Feb. 27, 2020 ...

As Season 21 of Grey's Anatomy continues to roll out new episodes, the total episode count for this series also continues to inch closer to the 500-episode mark.

However, since Grey's Anatomy has continued running for 21 seasons, the show has needed plenty of extra, outside actors to portray patients, bereaved loved ones, and sometimes, other doctors.

In honor of the medical drama debuting two decades ago, here's a look at the best behind-the-scenes photos from the cast of Grey's Anatomy. Camilla Luddington/Instagram From left: Harry Shum Jr., ...