You’ll often hear about actors and the role of a lifetime, but for Tom McKay and Luke Dale it’s especially relevant.

For the past nine years they’ve dedicated most of their working lives to two video games – Kingdom Come: Deliverance (KCD) and its sequel.

Added together, the scripts for the role-playing epics set in 15th Century Bohemia run to more than three million words, according to their makers.

It’s thought that KCD 2, which came out last week, could be the longest single video game script ever written.

Both actors spoke to BBC Newsbeat about what it was like to be part of such a huge project and working with the game’s controversial director.

The original KCD was something of a slow-burn sleeper hit. Its review scores were respectable when it released in 2018 but it wasn’t universally acclaimed.

However, it found a passionate fanbase in the months and years afterwards and the appetite for a sequel grew.

KCD 2 arrived to positive reviews and sold one million copies within 24 hours of launching.

The sequel follows the story of Tom’s character Henry of Skalitz, a blacksmith’s son turned knight, and Luke’s character, the impulsive Sir Hans Capon.

It’s a sprawling, open-ended game that allows players to carve their own path through it.

This means it’s possible to find important characters or items outside of the storylines that revolve around them, and the game will respond to these variable possibilities.

That’s something the game’s developers have to account for, and something that Tom in particular, as the main playable character, needs to act out over and over again with subtle differences each time.

It meant hundreds of hours of studio time and repeat trips to Prague, where developer Warhorse Studios is based.

He says it was “one of the most amazing and unusual acting challenges” he’s faced.

“You would kind of go down one channel of a decision and then come halfway back up and go down another one and then maybe all the way back up to the beginning and back down,” he says.

“And that’s not an acting challenge that you ever would have in TV or film.”

The video games industry is secretive, and both Tom and Luke spent three years under a non-disclosure agreement as they made the second game.

“It was almost like working for GCHQ or something,” says Tom, referring to the British intelligence agency.

“You couldn’t talk to anyone about it and people in the studio couldn’t even talk to their partners in some cases about what they were doing.”

Tom says he would occasionally bump into fans of the game when he was working on other projects, and would have to dodge the question when they grilled him about a sequel.

He says it was more difficult when he bumped into fans of the game in the Czech Republic, where the game is celebrated as a national success story.

When they asked why he was spending so much time in Prague, Tom admits he had to bend the truth a little.

“I’d be like: ‘I just love Prague. And I come here very often for lots of holidays,” he says.

Luke says many fans “gave up hope” that a sequel was on the way, given the six-year gap between the two titles.

But when the new game was revealed, he says, there was “this incredible reception and everyone went absolutely crazy”.

It also reignited an online discourse that had erupted around the release of the original KCD.

Daniel Vávra, the co-founder and creative director of Warhorse, is a regular poster on social media and is quick to answer critics.

He defended the first KCD, when it was criticised for its lack of diversity, as being historically accurate to the time and location of its setting, although there is not universal agreement about this.

At the time he also made public statements against perceived attempts to force diversity into games, saying his upbringing in communist Czechoslovakia had made him an opponent of “censorship in the name of good intentions”.

This won him supporters among the so-called Gamergate movement, which emerged online in 2014 and is widely seen as a backlash against attempts to make gaming more inclusive.

Members celebrated Vávra for his outspoken, uncompromising approach.

But as the release of KCD 2 approached some of those voices turned against him as it emerged that the sequel features a black character and a gay love scene that can play out if players make certain decisions.

“I think it’s quite a quite an interesting thing that’s happened,” says Luke.

“With the first game there was a backlash from a more left-wing mentality and then there’s been something of a backlash this time around from the right-wing mentality.”

Both Luke and Tom, having spent the days after KCD 2’s release meeting fans, say they believe the complaints are from an unrepresentative minority.

“It’s a really good barometer of the distortion between online interaction and real world interaction,” says Tom.

“We did nine hours and it didn’t come up once.”

Luke adds: “I think to be honest with you, the people that are true big fans of gaming and this game aren’t bothered about that sort of stuff.

“It seems to be people that are really politically involved and they care very much about politics and not gaming and they’ve just used this as a weapon, but they’re not necessarily into gaming.”

Both actors praise Vávra for his “forensic understanding” of his vision for the game.

Luke points out that, although the director had the final say, many people were involved with making the game.

“So you do the scene and you’ve got three four different people coming over to you,” says Luke.

“Can you do that? Can you just be aware of this?

“Me and Tom are like: ‘OK can we distill this down?’

“And Daniel is really good at helping us to do that because it’s his brainchild and he knows exactly what he wants every time.”

Aside from their relationship with their boss, the other question is whether the co-stars also get on after all that time together.

“Definitely,” says Tom.

“There’s something really organic about spending that amount of time together.

“So you kind of get that friendship for free.”

Luke adds: “It is like putting on a really comfortable pair of clothes.

“Which is ironic because in the motion capture studio you’re literally wearing head-to-toe lycra.”

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