Close-up on the 'most ambitious video game'
Thirteen people in Guildford are making the world's biggest video game.
No Man's Sky was first shown off this time last year, and back then it was just a shell of an idea, a grand promise to create Universe-sized game like no other.
"Great," everyone said, "if they can pull it off."
This year, we are finally able to enter that Universe.
It is a galaxy - no, several galaxies - created not by designers, but by algorithms: sophisticated mathematical formulas that generate unique worlds, meaning literally billions of planets can be discovered and visited in the game.
Mountains and rivers and lakes
No Man's Sky sprouted from the mind of Sean Murray, the founder of independent developer Hello Games.
He describes the game as his "mid-life crisis" - the result of years working on sequel after sequel at major games company EA.
He left to pursue a more fulfilling and creative career as an indie developer - and No Man's Sky is his baby.
"When I walk around this planet," he says, giving the BBC a guided tour of a world we have just casually discovered, "I don't see mountains and rivers and lakes, I just see the mathematical formulae."
He is alone in that. Everyone else sees vast, wild expanses of natural life - animals scuttling around in the grass, birds flying across the sky, lakes full of fish.
Once you comprehend that the beautifully designed landscape was the result of a formula rather than of human creativity, you start to realise the significance of what Mr Murray and his 12-strong team have achieved.
Last year, they were the unexpected stars of E3, given centre stage at Sony's huge press conference to show off what they had achieved so far.
So, this year, it was time to show they were capable of coming up with the goods, and to start to deliver on that enormous promise.
Their appearance onstage this time round was markedly more understated.
"When we showed the game off first, we definitely had a lot of hype around it," Mr Murray says.
"Hype is different to excitement. It's almost scary to a developer. Hype is an unattainable level of excitement. It will always lead to disappointment."
What's the point?
At E3's press conferences, every game is demonstrated as if it is the greatest epic ever created - beautiful graphics, with tense, gripping gameplay.
The games rarely live up to the theatrics of the trailer.
No Man's Sky's demonstration was a simple affair, consisting of Mr Murray, with a controller, playing the game for a few minutes - in front of thousands in the area and millions watching online.
He says: "We didn't pre-script it, we didn't have it like every other demo that ends with a gigantic explosion or something like that. We just said we'd stand up and play the game. If people are excited by that, then great."
The response was positive, but with an air of confusion. What exactly is No Man's Sky? What do you actually do in the game?
"There is a point," Mr Murray says. "You start at the outside edge of the galaxy. Every player starts on a different planet, they're trying to make their way to the centre of the galaxy."
As well as that core mission, players can pursue side-projects. Become a miner, perhaps, or even a pirate, attacking ships in space. You won't be short of things to do, Mr Murray says.
There are worries, though, that Mr Murray's team has seriously overpromised, and that the only path from here is one that leads to disappointment.
Developers with hundreds of employees would think twice about taking on a project as daring as this.
There is also a worry the game could be a bit, well, boring.
"The reality is the world we are creating is so huge, you are actually really unlikely to ever bump into anyone," Mr Murray says.
There is space combat, he says, and ground combat, and lots of side-projects to keep you busy.
But, while gamers will be no doubt mesmerised by the enormous scale of the game, it is an unforgiving community. If it is not fun, No Man's Sky is a dud.
The company seems to have a release date in mind, but it is not being made public just yet. Nor will Murray be fully drawn on the subject of virtual reality.
But in attempting to deflect that question, he fails to contain his excitement.
The company is looking at a virtual-reality version of No Man's Sky, so gamers can expect to enter this unique and ground-breaking universe one day.
It will be quite a journey.
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