In The Witcher, which begins where Sapkowski's saga adjourns, Geralt is unexpectedly alive but suffering from partial amnesia. You assume control of him during the tutorial prologue, which lays the foundation for what sounds at the outset like an unremarkable skirmish between good and evil. Thereafter, however, you're given exceptional narrative latitude to make morally sophisticated choices that actually (not just in terms of theme or mood) alter short- and long-term outcomes as you explore cities, swamps, sewers, castles and crypts. As troubles accrete, you'll have to dredge up Geralt's dodgy past and take sides in an all-out internecine racial war between humans and nonhuman elves, dwarves, gnomes and dryads.

Geralt's attributes, such as strength, intelligence, weapon proficiency and supernatural powers, are sculpted from ability-specific talents selected manually each time he levels up. In lieu of something more conventionally math-based, you select special skills like "cut at the jugular" or "poison resistance" or "blasting fist" that actually unlock those abilities, including fully choreographed combat kicks, spins and flips that alter the pace and flow of battles. Combat itself is click-driven and proceeds from a handful of offensive and defensive magical spells (called "signs") and three fighting styles (heavy, quick and group), which can be changed with a key press before or during a battle. But instead of repetitive hacking, you only click once to initiate each attack, timing subsequent clicks to set up a fluid chain of interlocking combos that, when executed properly, turn Geralt into a deadly melee virtuoso.

Alchemy plays a much more significant role than in other RPGs, allowing Geralt to create potions that bolster his abilities or add extras like night vision or speedier health recovery. Learning the art of potion-making is incremental, with authoritative texts nicked from houses or purchased from antiquaries unlocking your ability to gather herbs from flora or providing bestiary entries that let you skin slain creatures. Mini-games like "dice poker" and "fist-fighting," which let you challenge various players for money or prestige, are threaded through the game's five chapters, complementing other optional activities such as modifying weapons with meteorite shards or curing them with special substances or running them over a grindstone to temporarily increase their effectiveness.

Beautifully grungy and ethically nuanced

Early in The Witcher you'll approach a torchlit crossroads and a group of men crowding and threatening to rape a young woman. If you choose to save her, then escort her to her grandmother's house, she invites you to meet her at the local mill at sunset "and bring a bottle of wine." Arrive on time with the proper libation and proper social graces and you'll trigger one of the game's naughtier bits, which, while scenically PG-13, makes no attempt to pretend that what you're seeing isn't sex. Say something vulgar, on the other hand (and most of the time you can), and you'll get the boot. None of which would be notable in a book or a film, of course, but in a game, this episode (and many more like it) stands out contrasted with a history of nonsensically violent but more or less sexually sanitary experiences.

The tenability of easy dichotomies like "good" and "evil" is itself at issue in The Witcher, and nothing is as it seems in Polish developer CD Projekt's inspired translation of Sapkowski's beautifully turbulent, oftentimes amoral universe. Friends can be (and probably are) backstabbing cult members. Guards and thugs alike turns out to be aggressive sexual predators (sex as a theme in general is something the game embraces, instead of prudishly whitewashing this most elemental of biological imperatives). Witches sell poisonous suicide solutions and craft voodoo dolls to compel siblings to kill each other. Barmaids and plenty more besides will sleep with you for booze, money, gifts, and occasionally just temporary infatuation. Pious religious fanatics turn out to be repugnant misogynists. Mages who can't control their powers become half-insane, slobbering oracles. And for all the wonderfully "un-Tolkien-y" alghouls and echinops and graveirs and bloedzuigers you'll grapple with, the most hideous monsters in the game aren't the ones with six or a dozen consonants crowding a single vowel, but other humans, like you.

I could go on about the combo-driven combat, arguably the best, most graceful, most visually and mechanically satisfying ever in a real-time action role-playing game. I could talk about the lovely technical enhancements to BioWare's Aurora game engine that ably translate game artist Damian Bajowski's stunning concept work into three glorious stand-and-stare dimensions. I'd love to write several pages alone on all the clever to-dos, like one where you have to scrimmage with a killer plant ... after drinking yourself three sloppy sheets to the wind. Or another, where you have to pursue a criminal investigation, complete with interrogations, bribes, cemetery spelunking, illicit autopsies and other bits of skullduggery.

The only thing worth grousing about at all is the game's roughness. Load times are pretty steep for all the in-and-out you'll do going door to door and area to area. Sometimes the game's nonlinearity works against it by screwing up sequencing such that you'll get a quest to do X from someone, then trigger event Y without so much as vacating the premises because you already did X. Other times it's just the way events unfold. The first major battle occurs after a cutscene but doesn't let you save, forcing you to walk through a bunch of dialogue and load screens every single time you die, which, given that particular battle's difficulty, is pretty sloppy.

That said, I'd probably play The Witcher with twice as many glitches. It's that unmissable.