Sitting in his office in the middle of the Leicestershire countryside, Craig Duncan is busy leading his crew on a journey into uncharted waters. Four years ago, the head of Rare Studios and his team of developers embarked on a quest to create a game unlike any other that had gone before. The way it has been made, how the storyline develops, the graphics, the humour – they are all unique.

The creation of Sea of Thieves, a highly-anticipated shared-world adventure game featuring pirates, ships and buried treasure, has taken longer than Sir Francis Drake’s voyage around the world, but that time has been well spent, and the wait is now almost over. However, when the game sets sail on March 20, there will be no smashing of Champagne bottles against the developers’ desks at Rare. Their work is just beginning.

“In all my years of making games, this is the first one where I’ve had to relearn everything about making games,” says Duncan, who has spent more than 15 years creating and releasing videogames, almost half of that as head of Microsoft-owned Rare Studios. Despite his extensive experience, the pressure to make great games is always there; add in the fact he is head of Rare – one of the world’s best and most iconic studios – and the upcoming release of Sea of Thieves might cause anyone else to run, screaming, into the woods that surround the company’s offices near Twycross.

But that’s not Duncan’s style. Sat on a sofa in his office and dressed in jeans, a T-shirt and a hoodie, he’s relaxed, even though a group of journalists is visiting the office to play the latest version of Sea of Thieves. Rare memorabilia from the past decade hangs on the walls; history is important here. In keeping with tradition, Duncan casually reveals that the company has created a master disc. “It’s like a gold master,” he says, comparing it to the first disc made by record companies from which all other replicas are made. “There’s a disc, it does exist, it has a version of Sea of Thieves on that you can play, but it’s probably out of date already.”

Events are suddenly moving fast for Rare’s 200-plus staff. The latest closed beta for Sea of Thieves has just ended, giving the company crucial feedback on how the game functions as people play it.