As with most games expos, the preeminent attention-grabbers tend to be the big games. At the recent Eurogamer Expo at Earl’s Court, London, there was little deviation from the script. Tucked away in a (relatively) dark corner, away from the the top-tier titles and burgeoning booths – packed with fans looking forward to their Christmas stuffing – lay a few as-yet unheralded gems. Among the golden nuggets – geographical feet apart, but a fiscal parsec away from the heavily-hyped software du jour – Introversion Software’s Prison Architect could be found. We took a sneaky look.

As you might have gathered, Prison Architect is a game about building prisons. In it, you’re handed a prison warden’s truncheon and the responsibility for managing the day-to-day to-and-fro of the goings on within your jail. In the vein of Theme Hospital, the aim is to build an economically-viable business, while meeting the needs of inmates and investors alike.

One of the reasons I found myself parked in front of Prison Architect was the simple but striking aesthetic. The 2D, top-down penitentiaries look fantastic, even in their alpha-build state. The lock-ups are packed with busy, orange-clad inmates and feisty-looking prison officers. Each sprite has a pair of beady black eyes and a dumpy cartoon body – there isn’t much in the way of animation, but the way they bumble around the jail adds charm – leaving mucky footprints behind them, as they go.

The fundamentals work as you might expect: each institution needs certain structures and facilities to help it run as well as possible, from cells and generators to toilets and adequate lighting. The curio in the session we played was that unlike most games of its ilk, Prison Architect’s subject matter can be quite dark. The training portion involves constructing an execution chamber for a waiting inmate, guilty of the murder of his wife and her lover. The whole while, he and a priest sit in one of the cells awaiting the inevitable. As you complete each rudimentary objective, brief flashbacks of his path to the pen are recalled – polaroid snapshots and comic-book stills capture the moments before his arrest, as the prisoner tells of his motives, malice and regret.

At this stage, there’s little in the way of political choices to make, but during my chat with the developers, I was told that we can expect much more licence to build a slammer in our own moral image further down the line. I was also informed that we can expect anything from Darth Vader style dungeons to left-wing, liberal holiday homes – whichever best suits your mood.

Prison Architect is actually available to buy now, there’re several different price-points available, all of which grant you access to the game in whatever state it’s currently in. So far, there’ve been all sorts of comedic bugs – from inmates taking their lunch to the shower-room and eating naked, to ninety-six prisoners showing up in a prison van at once. If anything, these peccadillos are only likely to add to the experience, players who get involved early will have an opportunity to provide feedback to the developers – who seem very keen to involve their community in the games’ final construct.

For a game still in its infancy, there’s a promising intricacy to the environments. There’s already a hatful of different appliances – from the simple things like beds and bookshelves, to different foundations and floorings. Prisoners have a routine to keep, breakouts and fights can be commonplace, and keeping all this under control is fundamental to your success. There’re fires to put out and circuitry to maintain – from what we’ve seen, there’re lots and lots of things that can go wrong.

What might turn out to be Prison Architect’s defining feature – its addictiveness – is impossible to disregard. Being steered through the tutorial – full of flashing icons and rewarding smatterings of micro-objectives – was a pleasure. Introversion Software has already begun to knead together the ingredients that make great games hard to put down – barely a second passes without a tangible challenge or reward. There’s a long way to go before this game reaches its full potential, but the seeds have been sown.

Prison Architect comes from a strong lineage, with developer Introversion Software having been responsible for Uplink, Darwinia, DEFCON and Multiwinia over the last decade or so. This newest offering looks set to stand up with the best of them.