"There was an arrogant assumption that players of shooters didn't want and wouldn't care about a story; we just didn't believe this": Go behind the scenes of Half-Life with legendary Valve designer Marc Laidlaw

It could have all gone so wrong. We know you hear that a lot in game retrospectives, but this is serious. Yes, BioShock could have been about zombies in a Nazi bunker, Borderlands could have looked like gruel, and Tabula Rasa might have featured butterfly-winged men fighting each other with books. But Half-Life is more than just a game. It triggered a movement: a massive change not just in the way first-person shooters were made, but video games as a whole. It set new standards for player immersion, narrative quality, and combat AI, and opened the doors to modding in a more generous fashion than any other shooter had done before – in doing so, ultimately creating an unstoppable multiplayer phenomenon. In some ways, Half-Life is the most important game of the past three decades. And yet it might just have been a middling old Quake clone starring a guy called Ivan the Space Biker.

No, really. Ivan was a paunchy chap with a full beard and a flattop. He wore a bulky HEV suit and was, presumably, predisposed towards biking in or near space. One can only summon up that ever-mysterious deus ex machina known as 'the creative process' to justify how this blockily rendered slab of mid-Nineties cheese transformed into Gordon Freeman, the world's sexiest physicist, but there it is. Somewhere along the line, Half-Life went from embarrassing to exceptional. One of Half-Life's designers, Marc Laidlaw, attempts to explain: "We didn't so much 'pick' the current image of Gordon as just naturally develop it. Our artists reworked their concepts again and again and again until they had something we liked, and Ivan was just one of those concepts."

Return to Black Mesa

Such is the nature of early concepts, we suppose: those undercooked, malformed designs that so often unfortunately get foisted upon the gaming public due to tight production schedules. Luckily, however, Valve was self-funded by Microsoft vet and CEO Gabe Newell, who was more than happy to let his company's labour of love grow into its full potential. This culminated in a major overhaul fairly late into development, when the Valve team took stock of what they were building and decided it didn't stand a chance against Quake 2 and associates.

"The game was fairly close to completion," Laidlaw recalls, "and we looked at it and realised that if it were to be released, it would be completely lost in any number of competing products. So they decided to risk pushing the game's release back and do a complete redesign. We weren't beholden to a publisher holding the purse-strings. There were lots of other extremely talented and creative shooter developers out there at the time, though, but I think it just comes down to our own interests and talents. That's why it was different."

While we'd be quite surprised if you've never played Half-Life, there's always the chance that the pressures of time have rendered you unable to recall precisely what was so unique about it. Shall we start with the tram ride? Prior to Half-Life, shooters were devoid of context: there wasn't any sensible reason given to excuse or explain the mass murder the game would necessitate. For instance, when designers on the original Doom pitched a sequence to John Carmack where the player could watch his fellow marines enjoying a game of cards before being eviscerated by cybernetic hellspawn, he replied that "story in a game is like a story in a porn movie. It's expected to be there, but it's not that important."

How, then, must Carmack have felt in those opening minutes of Half-Life, where the player is confined to a tiny tram car, unable to do anything but shift from seat to seat, take in the underground view and listen to that valium-voiced female announcer? And after that, a solid ten-to-fifteen minutes of pure, weapon-free exploration within the Black Mesa Research Facility, where you do battle with such monstrosities as malfunctioning vending machines and shrill whitecoats reminding you you're late for work? Back in 1998, this wasn't just heresy: this was completely unthinkable.

A quiet revolution

In those opening minutes, Half-Life turned its back on the excesses of its contemporaries, and in doing so set the tone for the rest of the game (and for all shooters to come, other than maybe Serious Sam). Exposition, hitherto relegated to cut-scenes or walls of perfunctory text à la Doom, took place completely from the player's eyes. This had the effect of seamlessly integrating Half-Life's plot with its shooting; story wasn't treated as a necessary evil or a reward for 20 hours of mindless killing; rather, it was just as integral to the game as the gunplay.

"It was a radical change," Laidlaw agrees. "I played Quake 2 while we were doing Half-Life, and, sure enough, it starts with the player making his way out of a wrecked spaceship, blaster in hand. So, starting a shooter without giving the player a weapon, and then making the player explore an area completely devoid of threats for up to an hour, just wasn't done in other shooters at the time. It made me feel that we were taking a huge risk, and that Half-Life would be very different to anything else out there. But if it worked, I knew the rewards would be huge. We were all big fans of the FPS. It was, at least at the time, my favourite type of game, and one that seemed as if it would get the biggest benefit from the integration of storytelling techniques. There was a general arrogant assumption that players of shooters didn't want and wouldn't care about a story; we just didn't believe this."

Of course, due to Half-Life's player-centric modus operandi, Valve was required to create an entirely new way of telling video game stories. Because players were never saddled with two minutes of helpful pre-rendered dialogue warning them of the imminent alien security breach, or the arrival of the sadistic military unit flown in to clean it up, they relied on the frantic snippets of information that surviving Black Mesa scientists and security guards provided. Half-Life, thus, wasn't so much cinematic as realistic.

It was the first game that felt genuinely real, albeit with added extraterrestrials and at a top-secret research facility into which us Cro-Magnon hominids could never dream of being invited. "For a lot of people," Laidlaw, who was the story's chief architect, notes, "Black Mesa was a real place. The story actually stemmed from our desire to make coherent a large amount of in-game levels, which we really did design with gameplay in mind. The levels were all quite different, though, so the story needed to give voice to a team of level designers who'd never worked together before and would be fairly independent of each other whilst still having a common goal in mind."

The engine room

"After a while, when the levels were getting closer to their finished state, we started fleshing out the story," Laidlaw continues. "But we really had one goal in mind from the beginning – to have as little obvious explanation in the game as was possible. Players had to be the detectives, putting the different pieces together themselves. From what we've seen over the years, Black Mesa made a huge impression on a generation of players as a result."

All this emphasis on story isn't to suggest Half- Life wasn't also a technical achievement, however. In order to create Black Mesa, Valve was forced to drag the ageing Quake engine out of the morass for which it had become famous. With id bringing out their own sequel to Quake – and brand-new, Carmack-devised technology with it – and Epic MegaGames introducing the world to the soon-to-be-ubiquitous Unreal engine, competition was fierce, and perhaps a little daunting for the Bellevue-based newcomer. But GoldSrc, the engine created from Quake's ashes – and the modern-day Source engine's ancestor – proved more than up to the task.

"The biggest advantage in starting with the Quake engine," Laidlaw says, "was that we were allowed to get right into making the game, rather than spending several years building the engine technology first. A lot of our level designers were experienced Quake modders and mappers too, and understood the engine's shortcomings and strengths."

"Of course, there were some issues. The fact that the engine was changed so many times from the original meant that the designers were constantly catching up. They'd be stuck in this situation where they were waiting for new features to come down the line rather than just building prototypes straight away. And it wasn't really until the engine was finished that they were able to get productive with it."

Famously, Valve had planned on integrating real-time physics into Half-Life's many puzzles – themselves an innovation within the then fairly limited shooter genre – but were deterred both by the size of the task so late in development and the car crash that was DreamWorks Interactive's Trespasser. Still, what remained was above and beyond any other FPS available on shelves. In hindsight, yes, it probably wasn't as beautiful as Unreal , but what Half-Life lacked in graphical chops, it made up for in its (still) astonishing AI.

The military enemies in the game were Valve's primary AI showcase – and at the right difficulty, they're still some of the cleverest grunts both in video games and the world of flesh and capillaries. A lone commando was bad enough, but in groups they demonstrated an alarming amount of co-operative intelligence, seemingly changing their strategy on-the-fly as they attempted to outmanoeuvre the player. Valve has never revealed the secrets behind Half-Life's AI, and, curiously enough, the Combine soldiers of Half-Life 2 seemed more behaviourally staid in comparison. Demonic possession, perhaps?

A legend is born

It was the juxtaposition of Black Mesa's sterile blues and the pallid flesh-white and claret of Half-Life's monsters that made the game so aesthetically memorable, which may go some length to explain why many players found the penultimate chapter, set on the alien planet Xen, a bit boring in comparison. Still, they liked it enough to create countless mods extending the storyline while Laidlaw went to work on creating an even more oblique and surreal plot for Half-Life 2. And that was only the tip of the iceberg – quite apart from Half-Life's breathtaking single-player component, Valve also managed to foster the most formidable user-content community the games industry has ever known, one which ended up spawning two of the most successful multiplayer games of all time: Team Fortress Classic and Counter-Strike.

It isn't too difficult to see why Half-Life made such a deep impact on the gaming landscape, which is undoubtedly why Laidlaw remains surprised that so few developers have followed in Valve's footsteps. "I must say," he explains, "it was a lot fewer than I expected. I suppose it's a risky endeavour, and the narrative rules we implemented should only be done so if you know you're going to get something good out of it. That said, I've seen a lot of examples where Half-Life's influence is applied in a piecemeal fashion – Medal of Honor, for instance, and Call of Duty both followed those principles, but it was inconsistent. There were moments of non-interactive exposition interspersed with the dynamic parts."

Perhaps, though, it's simply that Half-Life is much more pervasive than even Laidlaw realises. The game's core principles of dynamic expression, first-person puzzle solving, and narrative depth have colored everything from Halo to Metroid Prime, and it's now becoming increasingly difficult to remember where it all came from. And on a more wistful note, now that popular game design prefers emergence over scripted sequences, and open-endedness over tight, contained level design, it may well be that Half-Life marked the beginning of an era that is soon to close. Will it be consigned to the scrapheap of irrelevance, then? Unlikely: Ivan the Space Biker's just going to have to get used to keggers with Duke Nukem and Crash Bandicoot, because Gordon Freeman was meant for better things.