(NEW YORK) -- Tom Cullen knows his way around a period piece. The Welsh actor stars in not one, but two, historical TV series this month: Knightfall, debuting on the History channel tonight, and Gunpowder, premiering on HBO December 18.
In the 14th century-set Knightfall, Cullen stars as Knights Templar leader Sir Landry, a warrior who gains newfound purpose when he learns the Holy Grail has resurfaced. Cullen says he was meticulous about getting the historical details just right.
"I just think if you're doing a period piece like this, you have to bathe yourself in as much literature as possible because you owe it to that time period," he tells ABC Radio. “I think that if you don't, it's lazy."
Part of that historical accuracy included the costumes. Cullen was outfitted with 50 pounds of authentic chain mail armor, which had the added bonus of getting him into amazing shape by the end of the shoot.
"I doubled in size," he says. "Like, it was insane. I put on 30 pounds of muscle. And just walking up stairs, you're squatting, so my a** at the end of this shoot was unbelievable. Kim Kardashian's got nothing on me!"
In the upcoming miniseries Gunpowder, about the failed London Gunpowder Plot of 1605, Cullen stars as Guy Fawkes opposite Games of Thrones’ Kit Harrington. He jokes that working opposite Harrington was tough because he’s so “hideous.”
"No, I'm a huge Game of Thrones fan and I'm a huge Kit Harrington fan and we're great friends and it was a pleasure to work with him and he's incredible in Gunpowder," he says. "I think it's his best performance yet and I'm very proud of Gunpowder. It’s a very cool show."
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