The stars of Grey's Anatomy... they're just like us! Meaning, they've totally had the awkward experience of turning into complete fangirls (and boys) when they come across celebrities, despite trying to play it cool.

Grey's has had its fair share of A-list guest stars and guest directors over the years, and TVGuide.com recently sat down with Chandra Wilson and Jason George, who play husband and wife Miranda Bailey and Ben Warren, to remember some of their favorites.

Grey's Anatomy: We finally meet Owen's sister!

We've seen plenty of tears shed on camera by the cast members, but which guest star made Wilson cry (in a good way) while she was still in hair and makeup? Check out the video above to find out. Plus, discover what struck George as particularly odd about the way his female co-stars behaved when Denzel Washington stepped in to direct an episode.

Grey's Anatomy airs Thursdays at 8/7c on ABC.