If you do an IMDb deep dive on 3 Body Problem, you'll see there are a lot more Game of Thrones alums involved in David Benioff and D.B. Weiss' new Netflix sci-fi series than those who show up in front of the camera. Those names extend from production designer Deborah Riley to composer Ramin Djawadi.

"There's tons of people who spent so much time with us in Belfast on the set," Weiss tells EW, referring to where they shot much of the hit HBO fantasy series.

Based on author Liu Cixin's internationally popular book series Remembrance of Earth's Past, the duo's new drama with fellow showrunner Alex Woo begins in China amid the 1960s Cultural Revolution, when a secret sect of the government is attempting to make contact with alien life. One woman's decision sends ripple effects into the future, and in the present day, those same aliens have targeted some of the world's brightest minds.

There are three Game of Thrones stars who are easily spottable in 3 Body Problem: John Bradley, Liam Cunningham, and Jonathan Pryce. Though, there are even more vets who made appearances in the adaptation than you might think.

Netflix

After playing Jon Snow's kind-hearted, reserved friend from the Night's Watch, Samwell Tarley, Bradley takes a more prominent part in 3 Body Problem. As Jack Rooney, he plays a member of the Oxford 5, a group of scientists from Oxford who become entangled in alien affairs.

Weiss and Benioff eyed him for the new series after seeing how Bradley carried himself at the Crown Pub in Belfast. "We wrote [the part] for him before we even told him," Weiss says.

"Well, we said, 'Don't take another job. We have something for you,'" Benioff adds.

Unlike some of the others in the Oxford 5, Jack isn't technically a member of the scientific community. Instead, he used his physics degree to develop a new brand of snack food and launched his own snack empire. The character in the novels on which Jack is based has a much smaller part to play than in the series, but Weiss and Benioff thought, "What if he had a bigger role and what if it was John Bradley?"

"We saw John talking to an American tourist who recognized him from the show," Benioff recalls of that Belfast pub meeting. "The real John is very funny, very caustic, sarcastic. We also had the pleasure of going to the Oxford Speakers Union. It was the two of us, Kit Harington, and John. We ended up letting John do about 70 percent of the talking because he's so much funnier than the rest of us, and so smart."

Ed Miller/Netflix

According to the showrunners, Cunningham was set to act in a competing project, but he ended up dropping that for 3 Body Problem once he was pitched the role. The actor behind Ser Davos now stars as Wade, the leader of the world's most powerful intelligence operation that's actively trying to suss out the alien threat.

"The books describe Thomas Wade as being 40 years old, devastatingly handsome, resembling Hugh Jackman. So, of course, we thought Liam Cunningham immediately," Weiss joked during a Los Angeles screening event for the show in March. "It was a perfect comp."

"Liam is another one of those people who we truly love being around, and his work speaks for itself," Benioff chimed in. "Looking at everything, not just what he did on our show, [but] what he's done far and wide [with] ... many of the greatest directors who ever lived."

Ed Miller/Netflix

Pryce didn't fair well in the game of thrones, but perhaps he'll have better luck facing a galactic civilization.

After playing the High Sparrow and making life in Westeros miserable for Cersei Lannister (Lena Headey) and Margaery Tyrell (Natalie Dormer), the actor now plays Mike Evans, described cryptically by Netflix as "a passionate environmentalist turned billionaire oil tycoon."

"There are a lot of other people we'd love to work with," Benioff says. "It kind of feels like, 'Well, why guys? Those guys are your favorites.' As much as we love John and Liam and John, there's a lot of people on Thrones that we'd love to work with again. It has to be the right role. So hopefully we get to keep making shows and don't get fired after this one, and bring some more people back, more reunions."

Even with hair on his head and a fake bushy beard, there will be those who can easily spot the Master of Whisperers. Conleth Hill, who played Lord Varys (a.k.a. the Spider), pops up in a very small role as the Pope. Well, not the Pope. A version of the Pope that appears within an alien-made VR game. Hill shares a scene with Hong and Bradley.

"Conleth is Catholic, so we thought having him play the Pope would be either very funny to him or not funny at all," Weiss says. "Obviously, he thought it was fine."

"Everywhere we went when we were traveling for Thrones, Conleth would find out where the church was and go for Sunday services. He takes it seriously," Benioff recalls. "We had a role for the Pope. It's quite the earthly Pope. We were like, 'This isn't sacrilegious. It's a fake Pope on an alien planet. It's got nothing to do with the actual Catholic church.'"

Hbo/Kobal/Shutterstock

Bradley revealed the final Game of Thrones actor making a comeback: Mark Gatiss. An even more evasive cameo than Hill, Gatiss plays another video game character in the scenes with Hong and Bradley.

Gatiss played the role of Tycho Nestoris on Game of Thrones. Tycho was a representative of the Iron Bank in Braavos, where Ser Davos and Stannis Baratheon (Stephen Dillane) traveled to secure funds to support their war efforts. As it happens, Benedict Wong, Cunningham's 3 Body Problem costar, was previously in contention to play a banker in that same Thrones scene.

"I think it was for a role of a banker or something," Wong revealed to EW of the role Weiss and Benioff had offered him.

"You would've been in a scene with me!" Cunningham said. "In the Bank of Braavos."

3 Body Problem drops on Netflix March 21.

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