[Warning: This story contains spoilers from the season- seven premiere of HBO's Game of Thrones, "Dragonstone."]

Samwell Tarly (John Bradley) escaped the North. He saved Gilly (Hannah Murray) and her baby from certain doom on the front lines of the White Walker war. He stood up to his horrible father and stole his house's ancestral sword. He reached the Citadel in Oldtown, where he has more information at his fingertips than he could possibly read in a lifetime. Really, so much has broken in his favor in such a short period of time.

Why, then, is Sam so down in the dumps?

Oh. Right. That.

The season-seven premiere featured an extended sequence that shows the less glamorous sides of life for Sam in the Citadel — namely that his primary charge is cleaning out bedpans in the infirmary, which also double as vessels for stews and other foods. It's a visceral, stomach-churning montage, especially for anyone enjoying the premiere along with a nice meal. That aspect aside, it was Thrones at the height of its bathroom humor Game, a great showcase for John Bradley's comedic chops as Sam.

Beyond that montage, Sam was at the heart of a few other key moments in "Dragonstone." He assisted in an autopsy alongside Archmaester Ebrose, a new character played by the legendary Jim Broadbent, and the first person south of the Neck who actually believes Sam about the White Walkers — but still does not seem to want to do much about it.

Behind Ebrose's back, Sam enters the restricted area of the Citadel and learns some coveted information for the war effort: Dragonstone sits atop massive stores of dragonglass, a substance that could prove deadly against the White Walkers. Sam's discovery will likely put Jon Snow (Kit Harington) and Daenerys Targaryen (Emilia Clarke) on the same path, perhaps as soon as next week's episode.

What's more, Sam has another connection to the Mother of Dragons, in the form of one of her closest confidants: Jorah Mormont (Iain Glen), trapped in a Citadel cell, his skin showing advance stages of the deadly disease known as greyscale. Will Sam and Jorah bond over their shared fondness for the late Lord Commander Mormont? And will the maester-in-training stumble upon some form of cure for the Bear Islander's disease, or at least somehow put him back on Dany's path?

Speaking with The Hollywood Reporter, Bradley touched on all of that and more — but first, we begin by touching on something you really don't want to touch.

The premiere finds Samwell Tarly stuck in a sticky situation, so to speak. What was involved in filming that gross montage?

It was quite a long time shooting it. It was shot over a period of about five full days. We're talking about 50 or 60 hours of shooting all of that. It was quite an experience, really. For the first time in my career on the show, I was completely alone. It was weird to be working so closely with the director and shooting that sequence in these five-second bursts. It was kind of strange, just making sure you got those tiny little microscopic five second moments in the can, and then hand it over to the editors to stitch it into the montage that it became. I had no vision of what it might look like, no expectations of what it might look like. When I saw it at the screening [in Los Angeles], that was the first time I had seen it. It was kind of extraordinary, the fact that they could take these tiny fragments and build it into a narrative.

We didn't use real human waste. It was one step down on the unpleasantness scale. We used wet fruit cake, for all of the.... I don't know you say it politely. (Laughs.) That was wet fruit cake. It smelled fine, but shooting under lights for 13 hours or so, it can get a little nasty. I was reminded last night that while I was shooting that scene, everybody else on the cast was at the Emmys [in 2016].

You missed the Emmys to scrub the Citadel's toilets?

Everybody said, "The cast has to go to the Emmys for a week. Which is the story that can take care of itself?" So I was left completely alone scrubbing toilets for a week while they were on the red carpet. It's hard enough to take as it is, but then watching my friends and colleagues having fun out there? It's a lot worse. (Laughs.) But it was a memorable moment, and I knew it would be a memorable moment. We've never done a montage like that before. I knew people would be talking about it and I knew it would have an impact, but I didn't know how much. It was nice to kind of have such a set piece in episode one. It was a real treat.

The montage serves a comedic purpose, but a dramatic one as well. Just because Sam isn't up North, doesn't mean he's not facing the proverbial and, apparently literal shit.

Oh, yeah. Of course. It absolutely serves a real dramatic point. You're instantly seeing just how frustrated and disincentivized and disillusioned Sam is with the Citadel.

The honeymoon phase is over.

The honeymoon phase never even started! When he arrived in the Citadel at the end of last season, he was so happy to be there. He was feeling accepted for the first time. He was so happy he could fight the same battle as Jon Snow, but fight from his own environment. And then they put him in that cloth and set him to work on the bedpans. As soon as he gets there, he's put to work. It kind of feeds the narrative for the next few episodes and the rest of the season in a way. Sam isn't able, under the rules of the Citadel, to do the job he was sent there to do. He wants to be a proactive character and he wants to fight the same battle as Jon Snow. He wants to bring his own skills to it. And he knows time is of the essence. He knows the threat might be on the Wall already. He knows the army of the dead is coming. And he knows he needs to find key information. He knows that his time is being wasted. That frustration, to see that so instantly in the season and see that he is frustrated and that he's been sent there to do a job he's not allowed to do? That's important. It's a great moment of character development that's disguised in a bit of fun. It's not a waste of screen time. It's important to establish how Sam feels in the opening episode and moving forward regarding the Citadel.

There's a new character in the mix: Archmaester Ebrose, played by Jim Broadbent. What was it like, working with him?

He's the greatest. He really is. I've been such a fan of his for quite a long time. When [showrunners] David [Benioff] and Dan [Weiss] told me he was going to be playing that part, I was so excited. There's a part of it where you're getting to work with a hero. He's one of the most well-respected actors there is. So that was exciting. But there's a creeping sense of dread that you're not going to be able to hold your own against him, that he's going to trample all over you. He was a true joy to work with. We worked together really well. We found our rhythm and we found our way of working together quite quickly. He's very generous. He's very patient.

At the end of our time together on the show, I went to his trailer to say goodbye to him. I said: "Thank you, Jim. It's been a lot of fun." And he said, "Yeah. It has been a lot of fun." For someone who has had such a career and has been acting for so long to come onto our show and I and the rest of the crew could still make it fun for him, after everything he's done? That was a kind of heartwarming moment. I'll never forget that moment. Working with Jim Broadbent was as amazing as you could imagine.

Did you have fun playing with all of the guts in the autopsy scene?

It was fascinating! (Laughs.) I've always found human organs to be quite fascinating, that how we appear on the outside is so different from how we appear on the inside. Some of my friends can't watch surgical details on TV, but I find it grimly fascinating. They put this corpse together that was filled with all of this stuff that was so unbelievably lifelike. It was kind of exceptional. It's fun to do a scene with props and physical stuff to bend the dialogue around. I think Jim and I found some nice comic beats with that stuff. It was the first scene we shot together. It was nice to get our hands on that, so to speak, and play around with it.

There's a shift in the scene. At first, Sam must be so excited that someone believes him about the White Walkers. And then the Archmaester effectively shrugs his shoulders: "Winter comes and goes all the time, the Wall always stands." It must be a great disappointment for Sam. Should it make us skeptical of the Archmaester?

Certainly, yeah. For the people who populate the Citadel, these maesters and archmaesters, they're not the people Sam thought they were. He thought they would be people like him who know the importance of knowledge and the importance of applying knowledge, and how it needs to be applied in the face of a great war. They don't want to do any work. They're there to put their feet up and stay out of the way. Sam didn't think it would be like that. He thought he would be around like-minded souls. He thought he understood what part they could play in the threat and the outcome of the great war. That's not the case. Sadly for Sam, he's manipulated all of these situations to get to the Citadel, and he's still as much out in the cold as he was at Castle Black. His thoughts and theories and ways of doing things, [the maesters] don't want to hear about that. They're not as proactive as Sam. There's a sense of frustration: "I thought you were like me. I thought you were going to help me find and apply this information. But you're not going to do that." He quickly finds himself just as much a stranger as he's ever been anywhere else.

Sam and Jorah Mormont meet briefly in this episode. I know you can't get into what the future holds, but simply based on what we know about them both, how do you think these two characters would get along?

I think they would get along very well. There's a lot of similarities between them. They're both cerebral thinkers. They're both immensely loyal to the people they follow and stand side-by-side with. Their hearts can often get them both in trouble. They don't always follow their heads; they often follow their hearts and take risks, which sometimes pay off and sometimes don't. Their mind-sets are constantly in conflict with their heart and emotions, and so they sometimes have trouble containing those emotions. They both are romantics. Sam had the courage to reach out for Gilly, and Jorah couldn't quite do that with Daenerys. There are similarities between them, and I think that would help them get along together quite nicely, actually.

Sam discovers that Dragonstone sits atop a mountain of dragonglass. He says he's going to pass along the information to Jon. It got me wondering: does Sam know yet that Jon is King in the North? Does he know that Jon was dead for a few minutes? Has any of that news reached Sam yet?

No, I don't think it has! Certainly it hasn't been referenced onscreen. Sam hasn't referenced it on camera. I don't think he knows. But that's a great little bit about the dragonglass at Dragonstone. If you look all the way back in season five, there's a conversation about defeating White Walkers, and Sam tells Jon about dragonglass, and Jon says, "If we're going to kill the White Walkers, we're going to need a mountain of dragonglass." Well, Sam just discovered that there's a mountain of dragonglass at Dragonstone. The thing I like the most about that moment is that even without the support of the other maesters, that they don't want to search for this knowledge, Sam is able to justify his reason for being at the Citadel. He repays Jon Snow's faith in him. He's able to send him key information: "There's plenty more where this came from." This could effect the entire outcome of the war, potentially, and that's very exciting for Sam. It's confirmation that when Sam goes looking, he comes up with gold.

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

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