06/05/2015 07:15 BST | Updated 06/05/2015 07:59 BST

'Game Of Thrones' Star Kit Harington Admits He Hadn't Watched 'Spooks' TV Series Before Starring In The Film

'Game of Thrones' star Kit Harington will be delighting his many fans in his latest screen outing - as solitary MI5 agent Will Holloway in the big screen version of 'Spooks: The Greater Good', but he's made a surprising confession, that he hadn't actually seen one episode of the long-running hit TV series before he started filming its cinema spin-off.

Kit tells HuffPostUK:

"I never saw the series and, once I was cast, I was told not to.

"When we started talking about the movie, I spoke to my friends who had watched it, and they loved it, and I could see from their passion for it, that it was good.

"But my character was nothing to do with the original characters, so the director told me not to, to look at it afresh, and I decided to treat it as a separate, stand-alone story."

Kit Harington stars with veteran 'Spooks' star Peter Firth in the film which has all the TV show's familiar elements

Despite this, Kit is relishing the moral ambiguity in the film that shares the DNA of the show, where some of the most central characters in the UK's security services turn out to have their own, very separate agenda. In the film, Peter Firth's character Harry Pearce is the veteran spy under suspicion, and Kit's character Will raises a few eyebrows with his actions too...

"He's basically a goodie with a bad, renegade side," explains Kit. "He has this rogue element, which was nice to play because I haven't done that before. Jon Snow is pretty much a good guy through and through. I wanted to play someone slightly less angelic which is what I got."

Ah, yes, Jon Snow, the 'Game of Thrones' hero that has made Kit a recognisable face - that hair! (which he's contracted not to cut) - across the land, something he admits can be a double-edged sword...

"It’s strange, everywhere you go, someone’s watched it, everyone wants to talk about Thrones when they meet you, and I guess that’s natural if they watch the show.

“But I don’t want to talk about it. I like filthy conversations, good old-fashioned stupid jokes.” (Fans, take note, this is evidently the way to Kit’s heart, or at least to him buying you a beer…)

Despite the lack of privacy that’s come with his role in the globally successful medieval romp, Kit only feels gratitude both for the friends he’s made on the show… “I feel part of a very privileged club, and we’re all very, very close”… and the career he’s hoping to build on the back of it. "Watch this space," is all he can say at the moment, keeping his cards close to his chest. Harry Pearce would be proud.

'Spooks: The Greater Good' is in UK cinemas from Friday 8 May. Watch the trailer below...