Gaming fans queued through the night for the long-awaited launch of Halo 3. Never heard of it? Rebecca Armstrong explains what all the fuss is about

This year's trio of box office big-hitters share a number of traits. They are all male, they all have special powers and they have fans across the globe. But while most of us have heard of a certain adolescent wizard and of a certain Spandex-clad arachnophile, the third member of this exclusive club is something of a mystery to most film fans and bookworms.

Everyone knows about Harry Potter and Spiderman; but Master Chief? The chances are that the name means nothing to you – even though, in commercial terms, he is as big as, if not bigger than, either of his rivals. The difference is that his fame is not down to a bestselling book or blockbuster movie but to a video game. But that game is, by any standards, a blockbuster.

When Halo 3 had its European release at midnight last night, thousands of people across Britain were in the queues to buy the highly anticipated – and hyped – Xbox game. And while Master Chief may still mean little to those who do not play such games, the one in which he stars looks set to overtake Spider-Man 3 and Harry Potter and the Deathly Hallows in terms of first-day sales. "When Halo 2 launched in 2004 it broke all box office records for any entertainment event ever," boasts Steven McGill, head of gaming and entertainment at Microsoft, the company behind Xbox.

"We're expecting Halo 3 to be even bigger and eclipse any entertainment launch, whether that's Spider-Man 3, which made $153m [£76m] in its first day, or even the latest Harry Potter book which made $156m."

The first two instalments of the game sold more than 15 million copies worldwide and Halo 2 made more than $125m in its first day of sale. Microsoft is confident that it will better that figure – and there are few people who would disagree. According to some industry analysts, Halo 3 will earn Microsoft $900m worldwide, an excellent return given that the game cost a relatively paltry $60m to make.

For anyone who hasn't played a video game since Pong was all the rage, it might seem preposterous that a game can go head to head with a Hollywood blockbuster and win. But to its fans, Halo 3 is more than just a game. On some websites dedicated to the game, players were yesterday swapping tips on "excuses to get out of work to play Halo 3" and "Halo 3 camp out plans". One enthusiast wrote that he was planning to take "My laptop, a USB HD tuner and the season premiere of Heroes," to pass the time while waiting to buy the game, while another planned to take a tent. The reason for this devotion is simple, according to Gavin Ogden, editor of "First and foremost, the game is fun to play," he says. It's also at the cutting edge of games technology. When Halo 2 launched, it wowed the world with a new way of playing video games – online, against friends and strangers, using the ground-breaking Xbox Live service. With Halo 3, the online aspect has been updated for a new audience used to user-created content and social networking. "Players can record films and take screenshots of absolutely everything they do in the game," explains Oli Welsh, a writer for the video games bible Edge magazine.

"They can then upload them and share them with other players. Halo 2 was the first big successful online multiplayer game on a console. I think the new features in Halo 3 are really going to set the bar for how gaming is going to evolve. You look at the big internet success stories of recent years – YouTube, Facebook – I think that Halo 3 is one of the first big popular games that's paying attention to what's happening in that field."

It is also the final part of a story that has been running for the past six years, and fans are desperate to know how the game will end. "It's the final chapter in the trilogy, so it is to Halo fans what The Return of the Jedi was to Star Wars fans," says Ogden.

Like Star Wars, much of the Halo series takes place in a galaxy far, far away. Our hero, Master Chief Petty Officer SPARTAN-117, John, or simply Master Chief, is a human soldier equipped with futuristic armour who must save humanity from a group of aliens known as the Covenant. The game is what's known in the trade as a "first person shooter" – FPS – and is billed as the best example of the genre. Over the course of the games, players explore Halo, a planet-like construction, and do battle on Earth with an array of hi-tech weapons and vehicles against a backdrop of hyper-realistic environments. It's a long way from Space Invaders, and playing any of the Halo titles is scary, exciting and challenging in equal measure.

And while it might not sound like a virtual War and Peace, the narrative of the Halo games has always been, according to many gamers, what sets it apart from other video games. "What makes it stand out is its story-telling," says Welsh. "Plus, people like spaceships and shooting aliens. Halo does that with really high production values and it's this high quality that sets Halo apart."

Halo's high production values are in no small part thanks to the fact that the company that made Halo 3, Bungie Studios, is owned by Microsoft. It bought Bungie Studios in 2000 and released the first Halo title – Halo: Combat Evolved – a year later. At the time, Microsoft's Xbox was viewed with suspicion by gamers and the company saw buying Bungie Studios as a way to win over its doubters. "Halo absolutely saved the Xbox," says Welsh. "Before the Xbox was released it was regarded with mistrust by the gaming community and the machine was almost a figure of fun. The first Halo title completely won everybody round and the Xbox and Xbox 360 have become the serious gamer's machines of choice." One of the reasons for Halo's popularity, he says, is thanks to the money that Microsoft throws at it. "Microsoft has a tremendous amount of muscle and a pretty unlimited budget and Halo is its chosen flagship, so it makes a very big noise about it."

The company has spent £5m promoting the game and with good reason. According to Ogden, "after only two games it's become a franchise thatMicrosoft says is worth $6bn to the company." Halo 3 is also increasingly making a wider cultural mark. Its fans in high places include film-maker Peter Jackson, who is co-writing, co-designing and co-producing a game that takes place in the Halo universe. Meanwhile, other games companies talk wistfully of creating Halo-killers, titles that could outsell Microsoft's record-breaking game, but few have managed to come close to replicating Halo's success.

However, despite the impressive sales figures, Microsoft is well aware that its rivals are snapping at its heels. Launched in December, Nintendo's Wii games console has become a surprise best-seller and its stable of games, all aimed squarely at families and casual gamers rather than Halo's army of hardcore gamers, has shaken up the games market in a way that few could have anticipated. "Halo 3 is the opposite of the kinds of games available for Nintendo's Wii," says Welsh. "Halo 3 is squarely aimed at the committed gamer and there's no doubt that it appeals to a mainly male audience in the classic teenage to thirties age range, whereas the Wii is aiming for that and everything but that." Thanks to its inclusive approach to gaming, the Wii has sold more in North America than the Xbox 360 and PlayStation 3 combined.

But back in London, the excitement surrounding the launch of Halo 3 is so great that Westminster council stopped a midnight launch on Oxford Street over fears of overcrowding. Nevertheless, 1,000 stores around the country opened their doors to fans as the clock struck midnight and at this very moment Halo fans across the globe are doing battle with the Covenant. And given that even now, three years after the launch of its predecessor, more than 300,000 people are still playing Halo 2 online, it seems likely that Master Chief will be big at the box office for quite some time.

Voices from the queues

Chris Franco, student, 20

"There's more anticipation about this game than I've heard about anything else; it's all we're talking about at college. The price is totally reasonable for an Xbox game, and I'd pay more than the asking price if need be."

Vu Nguyen, student, 22

"I'm so excited about this game I'm buying an Xbox 360 just for the purpose. All my friends have been talking about this for weeks. Given the Xbox 360 is at least three times more powerful as a console, Halo 3 will take this genre of computer game to another level."

Simon White, consultant, 38

"The special appeal of this game is that with link play over the internet you get the chance to play with friends and other users. Between you it's possible to feel like you've entered a whole universe of your own. For many players this game is a way of living out a fantasy."

Angela Bozio, foreign student, 23

"The graphics are incredible. You feel like you're in a whole new world, and there's something very satisfying about completing different missions, and getting a sense of achievement. I'm not a games console addict, but I do think this game will have popular appeal."

Tom Wieczorak, foreign student, 25

"The game is very addictive. A lot of people talk about the graphics, but the sounds it produces are absolutely incredible. They give you a real sense of being in another world."

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