Players take the role of Dr Jack Mason, a doctor tasked with rescuing a woman with a disease. Far from being a staid medical drama, Pariah is a futuristic FPS which sees Mason throwing the Hippocratic Oath out the window and going on a killing spree worthy of Master Chief.

The story of viral infection and aliens is intriguing enough, and provides enough twists to keep the narrative interesting throughout. It is portrayed rather well, although the audio for voices often sounds a little canned. The story tends to jump around quite a lot, though, with players ending up in a new area not knowing quite how they got there or why. More than anything this makes the story feel tacked on and built around a series of disjointed levels, which is something of a pity given that the story's premise was strong enough to support a compelling narrative.

While the game itself is quite linear most of the areas are wide open spaces filled with interesting vantage points and paths, making Pariah feel less restrictive than some other shooters. Opening the game are large forest areas that are quite gorgeous to look at, with small streams and rocks on the ground and sunlight prying its way through the lush foliage, with the battles appearing as quite an intrusion on this tranquil setting.

Later in the game the action shifts to more barren rocky outcrops or large, industrial cityscapes. While not quite as impressive as the opening few levels there is still quite a bit of detail and richness in these areas. Rarely will gamers feel that they are being funnelled through the mazes of corridors that characterise many FPS'. Right through Pariah the visual quality remains high, with Digital Extremes making good use of both the Unreal engine and the Havok physics engine.

The range of weapons within Pariah is quite small, but none of the weapons seems to be redundant as in those with larger arsenals. From the automatic rifle Bulldog through to frag and sniper rifles, pretty much the whole arsenal is fairly standard fare. Each of the weapons is able to be upgraded though, by collecting Weapon Energy Cores as the game progresses. These cores can then be used to add up to three extra abilities to each weapon. The Bulldog for instance, can be enhanced with a fire accelerator, a recoil stabiliser and armour piercing abilities. The upgrade system works quite well, with new abilities with abilities such as the remote detonator on the grenade launcher able to change the way the game is played.