Being Nathan Drake

The majority of these roles, though, are of the 'shuffling papers in a recording booth' variety. The lead performances in the Uncharted series stand out because of the palpable chemistry between characters - made possible thanks to the faith and finances of Sony in Naughty Dog's methods.

"We're in once or twice a week for an entire year," says Hennig. "For somebody shooting a television show they might shoot an episode a week - we shoot a couple of scenes a week.

"Everyone on the cast are friends, everyone on the crew are friends with the cast, so there's an ease of communication that makes us all feel free to constructively critique each other's work try and to improve it, and nobody's ego gets stepped on."

Of all North's roles, Drake is the most successful arguably because the line between actor and character in Uncharted is so blurred. Charismatic, handsome, funny and self-deprecating in person - everything, in short, a socially awkward Englishman should jealously resent - there's nothing 'phoned in' about North's performance.

"I get to learn their voices and write to them," Hennig explains. "I know their cadences, I know their idiosyncrasies. Their characters become infused by their personalities. With rare exceptions, the characters are very much [these] guys."

North agrees. "You can only be a Hannibal Lecter for so many days in a row. But if you're going to do something like this it has to become part of you after a few years. Otherwise it would seem contrived."

Central to this is the leeway afforded to North in particular to ad-lib. "I started theatre and stand-up comedy in New York," he reveals. "[Naughty Dog] let me go, take the leash off and I'm like a puppy in the dog park - you'll probably get 90 per cent crap, but there'll be 10 per cent that absolutely works."

"He's one of the most naturally funny people I've ever known," claims Richard McGonagal, who plays Drake's sidekick Victor Sullivan and is possessed of an infectious belly laugh that could loosen bowels.

"He's always coming out with funny stuff, and so what I do is just shut up, listen and react to what he says, so it gets this comedy dialogue going back and forth. But I just depend on him."

Unusually for an actor, North is involved in the casting process itself. "It's hard sometimes: it's a small community. There was a bunch of people that I knew reading for Flynn and they were great. And then Steve Valentine, who I don't know, came in and he was Flynn. You're just like, that's the guy!"

"You cast hastily or badly, you're screwed for ever," says Hennig. "You cast well and it's smooth sailing forever."

A key difference between Uncharted and many other games - including Rockstar's technically ground-breaking L.A. Noire - is that the full performance is captured at once - voice and movement - with all actors on set together.

It's familiar territory to anyone with theatre, TV or film credentials. The harder part of the job, according to North, is all the content gamers take for granted.

"The [actions] that are most challenging are the in-game ones," he says wearily. "If you're a player and the cinematic ends and Drake's like this [stands up straight], if you move that thing to the left, I have to do the move to the left, whether it's a run or walk.

"It's done right in the middle on this little board and it's exhausting, kinda tedious, but that speaks to the details. Because when you move that guy, the response is immediate.

He adds: "And we don't just play Drake and Sully. Sometimes I'm mo-capping the guy whose neck I'm breaking. Everybody kind of doubles up on that when necessary, so it's a real collaboration."