[Warning: This story contains spoilers through the second episode of Game of Thrones' seventh season, "Stormborn."]

Samwell Tarly (John Bradley) once again rolled up his sleeves and did the dirty work no one else was willing to do in Sunday's episode of Game of Thrones, "Stormborn." For the second week in a row, Sam was arms deep in bodily fluids — this time without a soaking wet fruitcake in sight, thankfully. What the sequence lacked in bedpan humor, it made up for in the sickening sight of Sam performing surgery on Ser Jorah Mormont (Iain Glen), suffering from an aggressive case of greyscale, a skin disease that eventually results in death, but not before the patient goes completely insane.

Last season, Daenerys (Emilia Clarke) sent Jorah out into the world to find the cure for his illness. His search brought him to the Citadel, where nobody except for Sam was willing to treat his condition. For his part, Sam's desire to help Jorah comes down to their mutual connection to the late Lord Commander Jeor Mormont (James Cosmo), killed at Craster's Keep the same night Sam rescued Gilly (Hannah Murray) from her lifetime of abuse and servitude. 

In performing the rare procedure on Jorah, Sam risks not only contracting greyscale himself, but also drawing the ire of Archmaester Ebrose (Jim Broadbent) and others within the Citadel. Go ahead and ask Sam if he cares. In earlier seasons, Sam wouldn't be caught dead defying the people in charge. But the Sam of season seven is another story. Here's what John Bradley tells The Hollywood Reporter about Sam's continued evolution this season, through the lens of that incredibly intense and disgusting surgery scene.

The Sam scenes this season have been ... let's go with visceral. What was your reaction when you first read the scene of Sam treating Jorah's greyscale?

I was very, very happy. I knew it would be another memorable moment, and a visceral moment, as you say — something that people are going to have a strong emotional connection to, and something people would be talking about. I was happy to be involved in something that was essential not just to my plot but also to Jorah's storyline and how it impacts the Daenerys story. It was nice to feel like a part of that and the wider landscape and story. I was really happy for Sam as well. He's taking matters into his own hands. He's being brave. He's defying authority. That montage you saw with him last week was very sad, because he feels like he's wasting time and he's not being put to good use and he feels like he's betraying his promise to Jon, all of these things. He's not having a positive effect on things. Then he had that dragonglass moment at the end of the first episode, and now he has another moment here where he can save somebody's life. It's nice for him that he's now fulfilling his promises and putting his skills to good use. He's having an impact on the way things work out in the grander scheme of things. So I was happy for two reasons: I knew the scene would be memorable and somewhat iconic and I was very happy to play it as an actor, but I was also pleased for Sam that he had this opportunity to help someone else.

What was involved in production? What were you sawing off of Iain's body?

It was a really quite tricky technical exercise. We have our amazing prosthetics department under Barrie Gower to thank for the visual element of the sequence. Iain had to get up at 3 a.m. every morning we were filming those sequences. He had to sit there in a prosthetics trailer while they applied these really detailed and intricate greyscale prosthetics, piece by piece. That was a very long process. When I was peeling sections of that off, I was basically peeling the plastic latex prosthetic off of Iain's actual body. He was kind of in a suit, and then there were a few parts with more give than what I could take off, which made it easier. It was the same as pulling away a prosthetic. It was a very, very big technical job for the prosthetics department. There were about five or six guys on set that day that you can't see but were just out of the camera line, there with pumps and buckets of pus. 

Oh, no.

Yeah, it was a really big operation. Barrie and his team did an amazing job. And it was a timing thing, too. Mark Mylod, our director, would count down from three, and when we reached one, I would open up the tiny little hole in the prosthetic, and at that exact moment, the guy with the pus pump let it go and it squirted out of the hole.

Oh, man.

It was amazing! (Laughs.) It was a real team effort. As I was pulling away at the prosthetic, they were pumping away and releasing more pus through the prosthetic. It looked disgusting on the day, too. It looks disgusting even when you know it's latex and that there's a man nearby with a bucket filled with creamy gunk. It looks so disgusting. You look down, and you genuinely believe in what it is ... you can imagine that it's pretty grim. Everyone really brought their A-game on that. When you're involved in something that technical, you learn the trust that the visual effects team has with each other. All of the craftsmen we have on the show, it was nice to get to see it in much closer quarters. It really kind of worked.

Courtesy of HBO

How was Iain through these shoots? He must have been very uncomfortable.

Yeah, it was uncomfortable. I tried to be very respectful of him. He had been up for five hours before everybody else. He had to sit there. It's quite a grueling process to have all of that applied to you, and you just have to sit back and stay still. It's quite a grueling experience to have four or five people swarming around you for hours at a time. I tried to be respectful in between shots and takes, giving him as much quiet time as I could. He needed to save some energy for the takes. It was a big job, to put across that level of pain and discomfort, the agony that his character is in. It's a big acting job.

Right. The noises he made were memorable. We won't soon forget the howling of Jorah Mormont.

Unforgettable. When you hear that, it really kind of pierces through your heart. The idea of a man being in such agony and being so uncomfortable ... it was so distressing to hear. So we were very careful to give Iain some time to breathe and rest up before the next take. I think he was exceptional. He was exceptional on the day, and the way Mark shot it and edited it, it was just such an interesting sequence. I'm so happy that I got to be a part of it and to share the screen with Iain Glen. I've admired him for so long. I think he's amazing. He's amazing on the show. It's nice to see these two characters interact. They do have quite a lot in common, these characters.

They're connected through Jorah's father, of course ...

Yeah, they have the link between Lord Commander Mormont, which is a nice thing to remind people of, and a nice way to articulate Sam's motivation and why he's risking getting into trouble and maybe risking contracting greyscale himself if it doesn't go well. He feels he owes a debt to Lord Commander Mormont, and that's what links those characters together. I do think there's a strong bond between them because of that. It was nice to play the part of meeting somebody you have this connection with, and somebody whose life you instantly want to save. There was something really beautiful about putting these two characters together. It was another one of the ways where the show can link two characters who you think have nothing in common, but it turns out they do and it's really lovely. 

Sam's family came back into the mix this week, albeit not on Sam's radar just yet. I know it was very important to you to have the chance to explore Sam's family in detail last season. When you walked away from that story last year, did you feel there was more story to tell?

I thought that it resolved itself pretty well. The whole point of Sam going back to Horn Hill, as far as an examination of the character is concerned, is how have the changes he's undergone affected him when he steps back into that environment? Will he be able to go home and look Randyll in the eye and tell him what he's achieved? "I've saved this girl's life, I've accepted the mantle of parenthood, I've been accepted by the Night's Watch, I killed a White Walker. I achieved all of this, and now you have to respect me. I'm no longer the boy I was. I'm no longer unworthy of your respect." Was he going to say all of that, or was he going to retreat into the boy he once was, where all of those achievements no longer matter? What you actually got was kind of both of those in a very satisfying way. Instantly, when he sees Randyll, he does retreat into himself and he does take the abuse like he always used to, and Gilly has to stand up for him. But then you get that moment of satisfaction where Sam takes what's rightfully his, something the father didn't think he deserved. Randyll doesn't think Sam deserves Heartsbane, but Sam does think he deserves it, because Sam thinks he's worthy of it and he's done enough to justify his position of having that heirloom and everything it represents. 

There is a sense of business being finished for Sam. He had to go home and touch base with his former self in order to appreciate just how far removed he is from that now. The taking of the sword was the ultimate satisfaction for him. Now he feels worthy of being head of that family and possessing the sword, even if nobody else agrees. It's a great moment of self-belief and self-affirmation. So I don't think he cares anymore. He knows what he is and he knows that Gilly knows what he is, and now he has this chance to be at the Citadel and make all of these differences and do this wonderful work. It's less of a presence in the back of his mind now. He's been able to clear out all of that emotional baggage. It's not playing a part in his character anymore. You can even see it in the way that he walks now. He doesn't shuffle around anymore. He holds himself with purpose.

Even in the way he speaks to Jorah: "You're not going to die today."

He really takes charge of that situation. He walks into the room and sets about his business. He's not tentative in that moment at all. He's not dancing around Ser Jorah in a reserved and hesitant way like he normally would. He goes in and becomes the boss of that room. He tells Ser Jorah what to do. "Drink that, bite on that, take off your shirt." It's a much more assertive side of him than we've seen before. We never even approached 10 percent of how assertive and confident he was in that moment. It's all about stripping away all of that emotional baggage. Actually, it's an interesting metaphor. He's stripping away Jorah's physical scars as he's shedding his own psychological scars. They're both shedding unwanted stuff. Jorah's is physical and Sam's is emotional, but they're both progressing. You can see Sam's progression this season already. He's no longer willing to be shat on by life. He's going into situations and taking control and doing things only because they're the right thing to do. I love that progression for him this season. 

Have we seen the grossest Sam scene of the season at this point? Or will we be speaking again next week because you were involved in yet another scene that brought Thrones fans to the cusp of vomiting?

I think in terms of vomit? That's pretty much it, I would say ...

Mission accomplished already, anyway.

Mission accomplished already. (Laughs.) Anything else would be kind of over-egging a little bit.

Watch the video below for the Game of Thrones cast's preview of season seven's battles.

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