History's 'Knightfall': How 3 men from 'Downton Abbey' are going medieval

History’s new drama series Knightfall doesn’t premiere until Dec. 6, but Downton Abbey fans who caught the latest trailer this week may already be excited: Yes, that’s Jim Carter (Downton’s Mr. Carson) as Pope Boniface VIII; Julian Ovenden (Lady Mary’s suitor Charles Blake) as William de Nogaret, right-hand man to King Philip IV of France; and Tom Cullen (Lady Mary’s scorned lover Tony Gillingham) as the series’s leading man, Templar Knight Landry.

The story unfolds in 1306, when the Knights Templar and their holy leader, the pope, uncover a clue that suggests the lost Holy Grail is in Paris. The Templars, whom showrunner Dominic Minghella likens to the Navy SEALS of their day, soon discover they’re not the only ones searching for the cup of Christ. Add in de Nogaret’s Machiavellian attempts to undermine the relationship between Landry and the king (Ed Stoppard), and the result is a 10-episode first season that Cullen describes as “House of Cards meets Vikings.”

Yahoo Entertainment has a first look at seven new photos from the series — and some teases to tide you over until its debut.

Casting Tom Cullen as Landry

“What we wanted, and what we saw in Tom, was somebody who you could believe is a fervent swinger of swords, and passionate believer in God, and that sort of front and center leader of men, but then at the same time who absolutely had an inner life,” Minghella says.

Those layers are what drew Cullen to the role (along with remembering all the times he pretended to be a knight as a child). “The show is called Knightfall, so at its heart it’s about a character who gets put through it,” he says. “He is somebody who’s struggling with his faith, and yet he’s incredibly loyal. He’s somebody that doesn’t want to be a leader, but is thrust into leadership. He’s somebody who believes deeply in his [celibate] sect, yet he’s having an affair with a woman. He’s somebody who would do anything for his brothers, yet he’s not telling them the truth. He’s somebody who is courageously brave, yet he’s scared to be himself. Those contradictions and those juxtapositions are, as an actor, what you dream of playing.”

Minghella credits casting director Debbie McWilliams with making both men’s dreams a reality: “She has always been the casting director for the James Bond movies, and if she can’t find you the next breakout hero, then you’re in trouble, you know?”

Cullen also enjoyed the physical side of Landry: “You look at something like Downton Abbey, you spend so much of your time just standing as stiff as possible, just saying words. But in a show like this, you get to just let rip. It comes off the screen at you. It’s so high octane and aggressive and a real thrill. For us to be on that journey for seven months, it’s the best job ever.”

One thing he didn’t initially appreciate, though: having to do all those action sequences in roughly 50 pounds of real chain mail (the rubber substitute didn’t look authentic under the lights). “I remember the first time we tried to get on the horses, we couldn’t because we just didn’t have the power in our legs yet,” Cullen says. “But doing like 16 hours a day in chain mail, my thighs and my butt are now enormous. I’m thinking of setting up this thing called the Chain Mail Diet, because it’s really in at the moment, isn’t it, big butts? People who want a big butt should wear the chain mail for six months, it’s all you need. I’ve had to change my wardrobe. I’ve got a wedding this weekend, and I tried to put on the suit trousers that I wore six months ago — couldn’t get it up over my knees. I thought, ‘What the f*** has happened?'”

Casting Jim Carter as Pope Boniface VIII

American audiences know Carter best as Mr. Carson, but Brits have long been fans of his work. “He’s been one of those fantastic British ensemble actors that whenever you switch on the TV, some old show, there he is being brilliant, there he is again being brilliant,” Minghella says. “And I bumped into him in North London. He was out walking with his gorgeous wife, Imelda Staunton. I just thought, ‘God, he’s brilliant. Wouldn’t it be great to have somebody like him in a key role for us in a show which, actually, is otherwise and deliberately and proudly peopled by actors who aren’t so known?'”

When Minghella thinks of Carter as Carson, he sees a symbol of all that’s great and good about England. “He’s a stalwart. He’s a reliable, fantastic, almost perfect, stoic, brilliant man,” he says, “and one of the things that’s like the most embarrassing thing that ever happens to Carson is that it gets out that he was once in a musical, and it was terribly shaming and hilarious. I thought someone who’s like that, who’s a really reliable sort of symbol of state, a figurehead for our Templars, could be really interesting — particularly if we’re then going to go on to tell a story that’s got a bit more intrigue than just an embarrassing youth in theater.”

Downton fans will also recall that Carson had a soft spot for certain people, like Lady Mary. “You could say part of what Knightfall is doing is church versus state, and he can straddle both in a kind of cuddly, reliable, good old Jim Carter-y kind of way. That worked for us early in Season 1,” Minghella says, “and then becomes more interesting as it evolves. So I hope it’s a nice journey for Jim.”

Carter’s casting thrilled Cullen, who refers to him as “the greatest man in the world.” He’d always wished they had more scenes together on Downton. “For the first day of Downton, I remember Jim was serving me some grapes and a haddock, or something like that, and I turned to him and went, ‘Thank you.’ And the historical adviser came over and went, ‘Don’t. Don’t say ‘thank you.’ ‘Oh, OK.’ So then he came over the second time, and I went [nods]. He went, ‘Don’t acknowledge him. Just ignore him, he doesn’t exist.’ My working-class polite manners — every time he came over, it’s like fighting the urge to look at him. So that was the most interaction I had with Jim [onscreen],” Cullen says. “And I remember the first scene we did [together on Knightfall], I was like, “Oh, it’s Mr. Carson with us,” but he’s such a great actor that within 10 minutes, I just completely forgot. … His character goes on this awesome journey, and Landry, my character, and his character have this fantastic, complex relationship that just bears some really great fruit toward the end of the season. I was so grateful to work with him — and I got to actually make eye contact with him, which was wonderful.”

Casting Julian Ovenden as William De Nogaret

The king’s conniving confidant needed to feel like he’s pushing people around a chess board without them knowing it. “He’s the guy who’s standing to one side but who’s actually totally screwing up your life,” Minghella says. Producers zeroed in on Ovenden’s intelligence and wit, which come out in his delivery. “Now that I’ve told you, you’ll notice this: He has a real gift in his phrasing. He knows how to carry quite complex dialogue — he almost sings it, and that’s because he is a singer,” Minghella says. “I don’t think it’s out of turn to tell you he is the queen’s favorite singer, and he performs at the Proms [an annual BBC classical music festival], and he’s a really fantastic musician, so he kind of takes this gorgeous, juicy delight in the delivery of some of the sweeter lines in the show, particularly as we roll on down through Season 1, which are kind of modern in his outlook. Because he’s the one character who is clear about his dislike of religion, and he feels as though he’s someone who can get power because his thoughts aren’t muddied by this kind of confused notion of god, whichever god it is that you pray to, and he’s got his own backstory which begins to make that understandable.”

While Cullen finally gets quality screen time with Carter, that’s not the case with Ovenden. “I think [our Knightfall characters] butt heads much like on Downton — through other people. We are enemies, but we never meet, necessarily,” Cullen says. “And it’s hilarious, because Julian and I are really good friends, and we really get on, but we seem to always be pitched up against each other. I think he’s one of my favorite characters in the show, by far. And that’s what I love about shows like this, that it has these great fight scenes but also has amazing political intrigue and interplay. And it has a really great love story at its heart.”

Knightfall premieres Dec. 6 at 10 p.m. on History.

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