When you arrive at the Japanese headquarters of one of the world’s leading games companies, you half-expect to be assaulted by employees wearing primary colours and bouncing off the ceiling. The first sight of Sega’s Tokyo HQ is encouraging: in the lobby there’s a statue of Sonic the Hedgehog, the company’s emblem since 1991, when he first appeared as the “cool” rival to Nintendo’s lovable Mario.

When I first came here, in 1992, Sonic was at the peak of his popularity. The first game had sold 4 million copies worldwide, and the sequel would go on to sell 6 million. I remember meeting the people who were then designing the games I would play a year later with something approaching awe. They mirrored this with embarrassment. Their office was just an office, they explained to me, no different from the one I worked in. The workers came in, did their job and went home. It was like banking.

These days, there’s more of a sense of a mission around the building. The interior decor is still a functional beige, but the basement now features a relaxation room, alongside a smoking area set beside an inclined Japanese garden. The intervening years have not been kind to Sega. In the 1990s it sought to capitalise on the booming home games market by releasing a slew of new machines without decent games to support them. In 2001, it withdrew from the console market, leaving the field to Nintendo, Microsoft and Sony. These days, Sega makes games for all three of its once-deadly rivals.

“I think the entrance of Sony and Microsoft changed everything,” says Masanao Maeda, Sega’s corporate director. “But in a good way. We were the first company to offer a portable colour video console, the first to bring 16-bit graphics, the first to offer internet play on a console, but I think we did new things a bit too early. We now have an advantage in software in that we develop all over the world for the international market.”

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The big game under hush-hush development today is Sonic Unleashed, which will be released on high-definition consoles later this year. In these drab offices, the walls piled high with computer equipment, a small team led by a remarkably cheerful Yoshihisa Hashimoto has been reimagining Sega’s blue mascot in 3D in adventures that will take him across the world. The pressure must be on? “Well, I was really happy to get the chance to reimagine the game in the way I want,” he says, “but as the news comes out that you’re in charge, the pressure mounts as you realise how many people are hoping you do a good job.”

As the deadline approaches, work on a game can involve days or even weeks of sleeping in the office (there are bunks for the purpose), followed by several months off as a reward. “I work so hard at this because it’s also my hobby,” Hashimoto says with a smile. I do hope he’s still smiling in four months.