Unforgettably disturbing images populate "BioShock Infinite," the most anticipated first-person shooter game of 2013. In the game, set largely in 1912, an interracial couple is nearly stoned by an angry white mob, a Chinese man is killed simply for being Asian, and Irish and blacks are relegated to separate bathrooms.

Out for a week, the third installment in a series from famed game designer Ken Levine has already been decreed a masterwork, and on the surface it's easy to see why.

Its mechanics are nearly flawless, and the narrative promises to realistically grapple with issues of racism, religious persecution and inequality. As with its two predecessors, it seems entirely possible that this installment is evidence that games can be thought-provoking.

"BioShock Infinite" is set on a magical floating city in the sky that seceded from the union around 1901. The city, dubbed Columbia, is a place where patriotism and religious fanaticism have run amok and moral values are questionable (thus the city's revered statue of John Wilkes Booth). The protagonist players control in this fantasy nightmare is hard-boiled detective Booker DeWitt. His mission? "Bring us the girl," he's told, "and wipe away the debt," a goal that isn't all that easy considering he has no interest in the place's nationalistic ideals and his memories have been stolen.

The game offers proof that shooters can make for a compelling narrative. Still, there's the nagging sense that for all its ambition, for all the care in crafting a fully livable world, "BioShock Infinite" is hesitant in what it wants to say. And raising tough questions is not the same as dealing with them.

The player is subjected to so much ugliness - propaganda preaching "racial purity," murals that call for keeping "foreigners" out of the city - that it starts to feel irresponsible having a character blast through Columbia without making any real choices about what he sees. The game, in fact, argues that individual choice matters little in the grand scheme of the universe.

Whether you chose to throw a stone at a couple because of their race or you attempt to save them from those who want to, the outcome isn't all that different. Yes, the couple will thank you later for making the clearly right decision, but it isn't integral to completing the game. The result is that the distressing realities of America's past - and present - are downplayed as they are turned into one-dimensional set pieces.

Many will play "BioShock Infinite" simply for its shootouts, and there's an assortment of vintage guns and magical potions to discover. As hectic as these scenes can get, it's one character - a woman - who adds depth to the action. Forget the fight scenes, watching a nonplayable character come alive and essentially drive the game forward is the most impressive aspect of "BioShock Infinite."

Elizabeth, the woman identified as DeWitt's debt eraser, turns out to possess the conscience that the cynical protagonist - and the game - lack.

Much of "BioShock's" narrative unfolds through conversations between Elizabeth and DeWitt. Moments, such as when the two stop and sing a hymn to comfort a child, are the heart of the game. It's so unlike anything seen in other action games that the go-to fight scenes actually become momentum killers.

She wants to save the world; he wants to save himself. "There's going to be revolution, just like 'Les Miserables,'" she excitedly says after discovering a rebel group ready to take down Columbia. To which DeWitt shoots back, "I don't want to be a part of it." Her round eyes shrink to a scowl, one of the all-too-rare moments where Elizabeth allows the player to feel ashamed of DeWitt. In a game where a magic elixir can summon a gaggle of murderous crows, it's the burning gaze of Elizabeth that has all the power.

Equally engrossing is Columbia's music. When a barbershop quartet or singer appear to pass by at random in this vibrant city, stopping and listening is advised.

Though it's the early 1900s, they're performing old-fashioned renditions of the Beach Boys' "God Only Knows." Later, a beggar sings Creedance Clearwater Revival's "Fortunate Son."

As it nears its action-heavy final acts, "BioShock Infinite" moves from attempting to make some sort of political statement to raising philosophical questions. Perhaps this is a function of form, because it isn't spoiling the game to say that it isn't long before DeWitt starts to feel like its central villain because of his cynical isolationism.

Players, for instance, hear the Chinese man being tortured, but they are too late to save him. When his attacker is hunted down, his corpse, as with any dead body in any first-person shooter, is simply raided for inventory - cash, weapons, potions, etc. The hunt for loot renders earlier shocking images as routine as the point-and-shoot games with little to say.

So when "BioShock Infinite" in its final scenes abandons Columbia's richness for one of time traveling and multiple dimensions with enemy ghost-like creatures, it isn't a surprise, but it is a disappointment. No longer is this a story of two disparate people and how they navigate a senseless society.

As Elizabeth says, someone can be viewed as "a great hero, or the worst of scoundrels, depending on who's doing the telling."

Some will view "BioShock Infinite" as a cruel social commentary, others as a relentless action shooter. But ultimately, it's a cop-out, where complex questions about injustice, hatred and right versus wrong can be forgotten by simply jumping through a rip in time.

BIOSHOCK INFINITE

Publisher: Irrational Games / Take-Two Interactive

Platforms: PS3 (reviewed), XBox 360, PC

Price: $59.99

Todd Martens: todd.martens@latimes.com

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