Transcript for On set with 'Grey's Anatomy' stars for their 300th episode
So we're going to the O.R. Okay, so that will be in -- scrub room is in here first. Reporter: Ellen Pompeo knows her way around a hospital set. So I need to learn how to scrub. Reporter: Showing me the finer points of prepping for TV surgery. This has season and betadine on it, which is ant septic. So hold your arms up. Feels kind of good, actually. Yeah, uh-huh. The first time it feels good. The 30th time when your skin's raw? How long did you scrub for? That's pretty good. In real life they probably scrub longer. On TV we do it pretty quick, as long as the dialogue takes. Reporter: For 14 seasons, Pompeo's played from Meredith grey on ABC's "Grey's anatomy." Pick me. Choose me. Reporter: The show has captivated fans with dramatic twists and turns at Seattle's grey Sloan memorial. Tonight's "Grey's" hit a major milestone with its 300th episode and it did not disappoint. Goes to Dr. Meredith grey -- What is your favorite part of playing Meredith? I get to sort of be a superhero in scrubs and play an ordinary person. She's very real. And very Pompeo's character is the head of general surgery. When the show started in 2005, Meredith grey was a wide-eyed first-year intern. My agent first called and said, ABC would love you to do this medical pilot. I said, I hate medical shows, they make me anxious, I'm a hypochondriac, I can't possibly do it. He said, just do the pilot. Take the paycheck. These things never go. They never go. They never go. These pilots never go. And here I am. Reporter: After scrubbing in for over a decade -- Then you go in backwards. Yeah. Reporter: Pompeo knows how to be convincing in a fictional operating room. Put the gown on, put the gloves on -- It's like break dancing. Yep, uh-huh. Yeah, you go like this. Then you say "10 blade." With authority. "10 blade." 10 blade. Uh-huh, like that. Then whoop, and you tcut. I was good up until the whoop cutting part. You're hired. I'm hired! Reporter: Like Pompeo, Jesse Williams had become a breakout star. We are officially a -- Reporter: But real life is stranger than fiction. A flight attendant has looked at me when they needed a doctor and began to ask me or expected me to do it. I had to check one once, "You know I'm not a doctor. The one thing you know about me is I'm not a doctor." Reporter: Just the actors are convincing, so are props used in the surgeries which are remarkably life like. We have like a model, like a reproduction of Scott Foley's head. Because he played a character on the show many years ago. And his character unfortunately passed away. We still occasionally use that from time to time. So sometimes we're operating and we look down at Scott Foley's head while we're cutting him further down. Reporter: Three of the show original cast members -- Justin chambers, Jane pick Kins Jr., and Shonda Wilson, helped us pull back the curtain further. You can warn me before we walk in this room. Reporter: The highlight of the tour is the medical prop room. I think that was my patient. I don't remember the plot. But I remember that. You had the pen in I eye guy. I'm almost positive. I'm looking at hair. Oh yeah. I remember this one. This is like our surgery wing and our O.R., O.R. 1 is here -- All these walls move, they go up. Really? Oh yeah, to make it easy for us to shoot. If we need to shoot in that room in this direction, we fly this wall right on up. Reporter: Show creator Shonda rhimes has come up with some astonishing medical scenarios over the years. They research it. A lot of these cases you see we perform, they are actual cases. We've had some of the craziest things come through this hospital that you would ever want to imagine. Have you ever looked at a script and you're like, come on. All the time, right? All the time. All the time. Season 3, season 2, we had the passenger stuck on the pole. So if you move me, I'll die. And I was like, really? Sure. And then we shot it. You know, like I can't believe it. How much do you know in advance? What's going to happen throughout the season for your character? Oh, gosh, it's script to script. It really is script to script. You'll talk to the writers at the beginning the season, they'll give you an idea of where the characters might head. But things change on a dime. And we just rock 'N' roll with it. Reporter: The show is so collaborative that four cast members have gone behind the camera. Chandra Wilson has directed 17 episodes. She knows what she wants. It's the actress in her. She's like, you get here, you get here. She's really hands-on, push you that way. I don't sit back and wait and see what people want to do. Tell them what to do. You stand here, put your hand like that, turn this way. It looks like very hands-on direction. She's -- like a dollhouse playing. Reporter: Ellen Pompeo has also directed an episode of "Grey's" and it's a natural fit. I'm going to teach you how to be a doctor. Good, don't ask me any questions on the street. Don't ask me about football. Your finger. I need the doctor, fix my finger. Oh, ah! You're a doctor, why she running? You're a doctor. That shouldn't freak you out. Next here, speaking of
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