Just because the characters are knee-deep in serious drama on screen doesn't mean the cast and crew behind Game of Thrones don't make time for good hijinks behind the scenes. Showrunners David Benioff and D.B. Weiss recently told Entertainment Weekly about the best pranks they've pulled (or fallen victim to) while filming. Kit Harington and Hannah Murray (who plays Gilly) joined forces with the costume department to hoax John Bradley (Samwell Tarly). The pair staged a fake fitting for Bradley to model an outfit that looked less Iron Throne and more bad Renaissance faire. "We thought it would be great to make the costume ludicrous, but just believable enough to not know it was a gag — so he’d think he would be wearing this on screen," Weiss told EW. "[It was] all rental stuff, very Henry the VIII, with Tudor bloomers and a massive codpiece that wasn’t even the same color as the rest of the costume." Some of these gems sound almost Punk'd-worthy: Once the producers got word that Rose Leslie hated to sing, they wrote a bogus scene that included a Wildling tune her character Ygritte voices in George R.R. Martin's books. The cunning Nikolaj Coster-Waldau managed to pull off an incredible caper. When he learned that his character Jamie Lannister was getting a hair change, he wrote what Weiss described as an "Angry Actor Email," in which the star protested the change and said he'd change his hair to a style he felt best fit his character. Days later, Coster-Waldau sent the producers a headshot of himself with a buzz cut. “We thought we’ll have to get a Jaimie Lannister wig at last minute at tremendous expense,” Weiss said. “HBO’s lawyers were calling his lawyers…” The gag? The photos were five years old — the Danish actor hadn't cut his hair at all.