In a given year, there's rarely any title that can claim to feature completely new intellectual property.

This is largely because most games are engineered to reuse the most successful and beneficial attributes of previous games, and likewise, many developers have their own styles that are inevitably embedded into their works.

Such is the case with Dishonored. Despite being set in the newly-minted city of Dunwall, and despite featuring an entirely fresh cast of characters, environments and – in particular – a vibrant art style, there's something ever so familiar about the game. Comparisons to Deus Ex are inevitable, given that designer Harvey Smith has secured a leading development role. Raphael Colantonio, head cheese at Arkane Studios is also on board, having previously had experience with Dark Messiah of Might and Magic and BioShock 2, the DNA of which is clearly apparent.

Then there's the Thief series, Hitman, and Assassin's Creed, and that's merely in the basic mechanics of the game. Peeling back a layer of Dunwall itself reveals heavy architectural cues from Victorian London, a kind of steampunk-styled world full of dark alleyways, monstrous caricatures and diseased rats. Large horseless carriages powered by primitive electrical tram lines trundle by, sparks flying. It's Dickens and Rand. Verne and Orwell. Yet despite the multitude of various influences, Dishonored still forges its own path.

Dishonored: The Knife of Dunwall screenshots

Corvo Attano has a fairly significant problem. Having been framed for the murder of Empress Jessamine Kaldwin and unceremoniously thrown in prison to ponder his impending violent execution, any kind of opportunity for escape seems entirely impossible. That is until The Outsider appears. This shadowy figure is a deity who spots individuals likely to affect history and – for reasons only known to himself – grants them various magical powers. Corvo receives a suspiciously ornate mask and his freedom in exchange for service, setting the scene for an assassination mission at a local bordello.

The Golden Cat Bathhouse is an upmarket establishment catering to the needs of the more discerning individuals of Dunwall. Amongst these are the Pendleton twins, corrupt members of parliament and supporters of the very same Lord Regent who so enthusiastically sentenced Corvo. The brief is clear – enter the brothel and execute both siblings – however how this is to be achieved is entirely at the whims of the player.

For this demonstration, the first attempt to complete the mission featured a great deal of stealth. By using the Possession ability next to the wharf, Corvo is squeezed into the body of a fish, and swims underneath the wharf through a drain to reach the bowels of the target building. The Possession ability is tiered; at level one, rats, fish and all manner of animals can be controlled. At level two, humans can be occupied, with predictably hilarious results. The developers are quick to point out that there are perhaps seven or eight different ways to breach this building, but for now – and having successfully infiltrated the Bathhouse – Corvo reverts to human form in time to overhear various prostitutes discussing their next clients.

Dishonored: The Knife of Dunwall screenshots

Learning that the Pendleton Twins are indeed on the premises, Corvo stalks the hallways silently strangling guards before dragging their bodies out of view. Blink is gratuitously employed to alight on ledges, or instantly port across rooms, the more perceptive guards becoming spooked but otherwise unable to take action against a figment of their imagination. Dark Vision is employed here too – X-ray by another name, this ability can detect guards through walls and helpfully add a heat bloom to their movements.

Morgan Pendleton is located first. Cavorting with a scarlet woman in a sauna room, it's the work of moments to sabotage the main steam pipe. By opening a valve wide, the room is flooded with superheated vapour, gruesomely dispatching the hated politician and his unfortunate companion. But there are no punchy one-liners, no double entendres muttered covertly; Corvo is a man on a mission and there simply isn't any time for such levity. There's still one brother left.

Dishonored: The Knife of Dunwall screenshots

Custis Pendleton presents more of a challenge. He's located by peering through the keyhole of room on the upper floor of the building, the act of which reveals his animated conversation with a prostitute. Quick adaptation is necessary to murder the politician without alerting the many guards. By using Possession again, Custis is occupied, and Corvo is able to open the door to a nearby balcony and steer him up to the edge overlooking the wharf. Then, by quickly ending the Possession spell – reverting to Corvo – Custis can be hit with Windblast, comically flinging his body over the ledge and killing him upon impact with the ground below.

Corvo has no such problem with heights. As long as the player is suitably adept, our hero can leap from the highest ledge and survive provided a suitable body is identified and possessed on the way down, a sneaky skill only discovered during player testing and left in the game intentionally by the developers.

The stealth run-through of the Golden Cat level complete, it's time for the more violent version. By Blinking up to the top of the building, Corvo pounces into action, brutally slaughtering half a dozen guards with a combination of sharp steel, crossbow bolts and gravity. Every mission play through will find each brother in one of many different locations in the building, but with Corvo's rampage there's no time to stop to admire the scenery. Sure enough, both brothers are found in a fraction of the time as Corvo carves a swathe of destruction through each corridor and elaborately decorated room.

Dishonored: The Knife of Dunwall screenshots

Such enclosed, instanced levels will form the bulk of the mission content upon release, but Dishonored has another trick prepared, briefly hinted at with the reveal of The Flooded District. This derelict area is patrolled by Tallboys: human-controlled mechanical stilts armed with electrical pulse weapons and fearsome coordinated attack abilities. These guards present the greatest threat to Corvo thus far, however they're still human, and are therefore susceptible to the Possession spell. Now serving a new purpose, the spell is employed to move a Tallboy past an electrical defence network that would have otherwise fried Corvo, before destroying the contraption with some well-timed shots.

Dishonored has much riding on it for Bethesda. With Prey 2's development hiatus confirmed and Doom 4 absent without leave, it's looking like a slow release year for the publisher. It could be that Dishonored is pushed out the door quickly to get cashflow rolling, which would be disastrous for such a wholly compelling title with real developer pedigree behind it.

Or, Bethesda could recognise that properly managed, Dishonored could be the beginning of an epic franchise, and that however long it takes to polish it to a fine gloss is time well invested. We'll certainly see more at E3 in about a month or so, but even at this early stage the potential is staggering. Let's hope it's given free range to reach the lofty expectations ascribed to it.