The game mixes the Western, horror and steampunk genres, telling the story of Jericho Cross, an outlaw gunfighter in the late 19th-century American Frontier who has been turned into a vampire and forcibly recruited by the titular monster-hunting secret organization to fight against supernatural forces.

The game was accompanied by an extensive promotional campaign and was planned to be the first installment of a new media franchise, but its sequel got canceled in 2007 and the film adaptation remains in development hell.

Darkwatch features a reputation system that affects player's abilities in addition to the player character Jericho's starting, neutral vampiric powers of "Blood Shield" (a regenerating force field), "Vampire Jump" (a double jump that can be aborted at any moment) and "Blood Vision" (a system of thermal vision highlighting enemies and objects that also acts as a zoom).

[4] The powers can be activated for a limited time when the HUD's blood bar, which is fueled through collecting souls of the slain enemies, is completely full.

[5] During the daylight hours, Jericho's powers are gone, so he has to fight as a normal human, using a wide variety of weaponry, from a Darkwatch's standard-issue 24-shot Redeemer handgun to a crossbow firing explosive arrows and a rocket launcher, as well as melee combat.

In multiplayer matches, the players can pick up the "Silver Bullet", "Mystic Armor and "Blood Frenzy" powers as floating power-ups that activate immediately.

The game's story (narrated by Peter Jason[9]) follows the exploits of a former American Civil War veteran and wanted outlaw named Jericho Cross and his employment in an ancient vampire-hunting order known as the Darkwatch.

The game continues with the introduction of Darkwatch agent Cassidy Sharp as well as the appearance of Shadow, Jericho's undead horse whom he fed on and turned in a frenzy after being bitten by Lazarus.

[5] As the game progresses, Jericho finally makes his way to the Darkwatch Citadel, where he meets General Clay Cartwright, the current leader of the order.

Missions include tasks ranging from fixing some of the damage he has caused to acquiring Darkwatch equipment, such as the Darklight Prism, a stone that allows vampires within its vicinity to both use their powers and walk in sunlight.

[21] In the early derivatives of the project, the game "looked more like something from Pixar" and its protagonist was supposed to be Chaz Bartlett, a "vaguely bumbling sort of comic relief character", described as an "Eastern dude who was a card cheat" similar to Bret Maverick.

[11] The game's lead designer and writer Paul O'Connor said that the original 'high concept' for Darkwatch was "Blade meets Men in Black in the Old West", but "in the two years that the property has been in development, it has grown in other directions and taken on a life of its own.

[30] O'Connor said the game's reputation system was inspired by the contrast between the Old West figures such as Billy the Kid and the likes of Wyatt Earp, who "both were feared gunslingers, but one was a psychopathic killer and the other was a good guy/lawman".

[13] The developers licensed Ennio Morricone's main theme from the film The Good, The Bad, and The Ugly which was remixed to fit the horror feel of the game.

[32] Darkwatch was officially unveiled on January 12, 2004, its announcement accompanied by a showing of its playable multiplayer deathmatch mode,[33] and was originally slated for a Q4 2004 release.

[34] At one point, the game remained in limbo for several months until May 2005, when High Moon Studios, by then a fully independent development company, found a publisher in Capcom.

[54] She was also featured in exclusive pictures on the cover and the pinup poster of Play issue #44 in 2005[citation needed] and in the 2007 calendar The Art of Heavy Metal.

[56] A comic titled "Innocence", published in the July 2005 issue of Heavy Metal, serves as an immediate prequel and expanded introduction to the game.

Set in the Nebraska Territory, the story follows them as former partners reuniting for a mission to capture the tomb of Lazarus, an ancient vampire lord and Darkwatch's original founder.

[78] The game received the score of 7.9 ("Good") from both Bob Colayco of GameSpot ("If you're looking for an intense shooter experience, Darkwatch will not disappoint")[69] and Jeremy Dunham of IGN ("Cowboys, vampires, and sexy dead girls are fun in parties, but not so much alone").

[84] In 2010, GamesRadar's Mikel Raparaz ranked Darkwatch as sixth on the list of the top seven weirdest westerns, commenting that "the gothy trappings overlay a pretty awesome, Halo-inspired shooter".

[86] That same year, Robert Workman of Comic Book Resources called Darkwatch "in particular [...] a fantastic effort, a first-person shooter with beautiful, spooky atmosphere and excellent gameplay".

[88] Mark L. Bussler of Classic Game Room said in a retro video review that among many shooters on the PlayStation 2, "few are as fun as this", adding that Darkwatch should be "in your collection" alongside Red Faction and TimeSplitters.

[90] Darkwatch was supposed to be first of a series of games that would be set in different time periods, including Ancient Rome, the Crusades era and World War II.

O'Connor said they wanted "to tell not only the story of Jericho Cross but of the Darkwatch as an organization, from its origins in Roman times to its ultimate fate in Earth’s future".

[96] In 2011, it was reported that Glen Morgan and James Wong, the writers/directors/producers behind The X-Files and the Final Destination film series, "have developed a pitch based on the game's plot and action sequences, and are currently writing a screenplay".