If you ask a real spook, most mainstream spy movies range from the ludicrous to the eerily realistic.

Or at least, that's what American intelligence veterans told us at the International Spy Museum recently. According to them, "Mission: Impossible - Ghost Protocol" (now out on DVD) falls squarely in the middle: Most of the gadgets -- even those that fail -- are more fact than fiction, and the quick-witted way the team works together gets a thumbs up; but the Kremlin exploding and the climbing of the Burj Khalifa is pure fantasy. After some discussion, it seemed there was one spy film that all of them could agree was tops: "Tinker Tailor Soldier Spy," based on John le Carré's best-selling novel.

As for what doesn't work: any movie that focuses on graphic, widespread violence, maniacal agents or drop-dead-gorgeous vixens. "I've always been upset that most spy movies show spies as deranged assassins out there trying to off the American public!" said Jonna Mendez, former Chief of Disguise, aka "a real-life Q."

Here are five spy movies that the real-life spies found worth watching.

'Mission: Impossible - Ghost Protocol'

"This is a cerebral business. Bravery yes, athletic ability, yes, but it's the ability to build relationships that's what the spy business is all about ... As you look at this movie, it takes a lot of bravery to do the things that Ethan does, and that is a huge part of this business ... There's a certain amount of adrenaline kick that agents thrive on, like Ethan. But I'll tell you one thing: I can't imagine anyone I knew at the FBI crawling outside that building and dangling like Tom Cruise!"

-- David Major, retired head of counterintelligence for the FBI

'Tinker Tailor Soldier Spy'

"What's so realistic about this movie is that nothing was as it appeared. This is a cerebral people business, and the movie showed how smart the agents were, how they had to deal with double agents, how everything was layered and complicated."

-- Major, who also recommends the movie to his students in an intelligence class

'Knight and Day'

"I always look for the small details, and 'Knight and Day' was great. Obviously, it's a little self serving, since I had the pleasure of working on that film; but they don't have to take the advice that I give, so I never know until I see the movie. When I saw that one, I was so pleased at how realistic everything was."

-- Dale Shelton, FBI

'Red'

"It wasn't necessarily realistic, but it was so much fun. I loved Helen Mirren!"

-- Shelton

One movie that's not yet released:

'Argo'

The U.S. intelligence community is excited about the upcoming Ben Affleck-directed drama based on the CIA operation (sometimes called The Canadian Caper) to rescue six American diplomats who escaped capture when Iranian forces seized the embassy in Tehran on Nov. 4, 1979. Over two months, Tony Mendez, a CIA "exfiltration" specialist and chief of disguise (played by Affleck), worked with the Canadian government to devise the perfect cover story: the agents would pretend to be Canadian filmmakers scouting a Middle-Eastern feature film called "Argo." Mendez is consulting on the movie, which has a release date of September 14, 2012.

And one that got a thumbs down:

'Safe House'

"That had nothing to do with reality and was the bloodiest spy movie I've ever seen! Gimme a break."

-- Major