Sure, there's an element of disbelief when it comes to spy movies - but the likes of James Bond has always stretched the bounds of credulity.

Likewise, Jason Bourne and even the more ridiculous stuff like xXx have always been pretty fictitious. However, /Film to two real-life spooks - Peter Earnest, a 35-year veteran of the CIA, and Jonna Mendez, the former Chief of Disguise in the CIA’s Office of Technical Service - to see which was the most accurate movie out there.

Unsurprisingly, Tomas Alfredson's slow-burn thriller 'Tinker Tailor Soldier Spy' was the clear winner. "I was involved in counterintelligence," explained Earnest,  "and 'Tinker Tailor...' is very much a duel of wits. The bottom line of which is: you identify a traitor – someone who has betrayed your group. That happens in reality, and I have been very close to that. So the consequence of it, and the effect it has on people are very real to me."

Yikes, especially when you consider just how bleak that movie was and especially its ending.

The movie, released in 2010, was the second adaptation of John Le Carre's novel - who himself was a former employee of MI5 and MI6 in the '50s and '60s. Gary Oldman played George Smiley, a forcibly retired spy who's sent back into the service to hunt a mole that's been stealing intelligence secrets for the Soviet Union. The movie itself caught the mystery and the grim spectacle of spycraft, and is easily one of Gary Oldman's best performances.

Here's the trailer.