2.8 Hours Later is a city wide zombie-chase game devised by Simon Evans (wearing the cowboy hat in the picture) and Simon Johnson.

These ambitious, exciting and unforgettable events take the players into a world where the undead walk and terror hides in every alleyway.

We spoke to Simon and Simon about where the original idea came from, about their company Slingshot and what plans they have for future events.

HC: So is 2.8 Days Later your only jobs or do you have usual day positions?

SS: This is our only job. We started Slingshot over four years ago and in that time have produced over thirty games, of varying style and size, from iPhone apps to venue based spectaculars.

HC: Where did the idea for 2.8 Days Later come from?

SS: We run a festival of street games in Bristol each year and have done so for the last four years. Each year we staged a mass participation cross-city chase as the Friday night opening game. Each year the game got bigger and more ambitious until in 2010 we wanted to stage a multi-night, ticketed game. The coalition government had just got elected in the middle of a recession and we wanted to do something about profound and unsettling social change - we had images of abandoned schools, hospitals and police stations, the collapse of the public sector. Well, what’s the pre-eminent post-apocalyptic genre? Zombies of course.

HC: How did you go about producing your first zombie event?

SS: Like we say, the first event was the latest in a series of such annual games, so we had that experience to fall back on. We also had Bristol. The first few of these big games were all the result of a huge collaboration between the various communities that make up Bristol's amazing creative scene, all providing their skills and passion for free. So we had new circus production staff, artists building sets and street theatre performers, oh and let's not forget the cohort of volunteer chasers who we had attracted over the years. It's this support that enabled us to stage the first zombie game, along with the backing of the Watershed Arts Centre and the Pervasive Media Studio, the Watershed R&D studio. We also had Hazel Grian, an awesome writer who now works for Aardman. She was our secret weapon. We are bigger now, with income from ticket sales and paid production staff, but we still rely on volunteers to play zombies and to marshal, as well as the incredible commitment of our production crew and performers. No one gets rich working on this.

HC: Can you recall how you felt the first time you played the game?

SS: Surprisingly scared. Even though we knew the route, obviously, and where the zombies were, it really got to us. The first year, we left the start and immediately you found ourselves in a busy street of bars and members of the public. Pretty hard to imagine the zombie apocalypse with all those people around, but as soon as a zombie lurched out of the shadows the Saturday night city fell away and there we were alone with a zombie in an infested city.

HC: Why do you think these events are so popular?

SS: Well see the last question. We work hard to allow people to "imagine" another city, another world. We can't stop the buses, exclude the public or close the bars, but somehow that doesn't matter. The urge to suspend disbelief is powerful and wonderful. Of course the game is exciting and the adrenalin is a great buzz but the game is also really social. Some people come in teams, but many do not. As we start people in groups of six to eight we make up groups from strangers, where needed, and these groups develop an amazing esprit de corps, even though it's not a team game. The zombie disco is full of people swapping emails and Facebook contacts with their new best mates. I mean what is more bonding than having survived a zombie apocalypse together?

HC: Do you have a wide range of players meaning do they come from all walks of life?

SS: Yeah. We are really proud of this. We have a roughly equal mix of gender and a huge demographic and ethnic spread. We've had young hijab wearing Muslim girls in Leeds, middle-aged Brummie Goths, London design hipsters, Glaswegian council workers. It's humbling.

HC: Where do your ideas for scenarios come from?

SS: Our imagination, zombie films, computer games, games generally. Dreaming up games is our job, so we have quite a store of ideas. We have a white ideas room at Slingshot HQ. No furniture, just two beanbags. One wall is a huge blackboard, the other white board. That's where we dream stuff up.

HC: Has there ever been a city that didn't want you to play the game in their area?

SS: Hmm, we need to be diplomatic about this. Let's put it this way: some councils need a bit of persuading.

HC: What's the funniest moment you can recall from past events?

SS: There was a scene in an abandoned pub in London. In this scene, players encounter a bar lady who suggests they stay with her, have a drink and keep safe. Kind of a Winchester scene. Anyway, she says her boyfriend will be back in a mo as he is just in the cellar sorting out the barrels. Queen comes on the radio and well something scary happens (we don't want to give away a spoiler). This particular night a couple of Japanese tourists got in, not players, so they shouldn't have gained access, but they did. Guess they thought it was a cool bar so joined the queue outside. We always wonder what they thought when the other 'drinkers' exploded out the front door in terror.

HC: In your opinion what is the greatest zombie movie ever made and why?

SS: Shaun Of The Dead. Maybe the purists won't agree with the choice, but we show a clip of it at zombie school where we train our zombies and it still makes us laugh every time.

HC: Can you see these events getting any bigger?

SS: We are at capacity for each night of 2.8 but we are staging it in nine UK cities this year and more next, often with multiple weekends in each. We are currently designing the next big game, with a different theme and some really cool technology and this will have a larger capacity.

HC: What's next for 2.8 Hours Later and yourselves?

SS: More touring, with the USA a possibility for next year. There are also some interesting 2.8 side projects in other media planned for the winter months, when we get some time off touring. Another thing Slingshot is working on is the new big game for 2013. It's totally hush hush for now, but we are working with Nottingham University's Mixed Reality Lab to use some amazing technology in the game. Imagine a game that knows where you are in the city at all times and that changes your environment accordingly. That's where we are going.

The next 2.8 Hours Later event will be held from 16th - 19th May in Liverpool. Click here for more information.

Click here to read Horror Channel's Stewart Bridle's report from one of last years 2.8 Hours Later events.