Sony’s been airing an ad for “Uncharted 2: Among Thieves” in which a guy confides that his girlfriend can’t stop watching him play the game because, “she thinks it’s a movie.” Bogus Sony exec Kevin Butler, who takes the title “VP, big action moments” for the spot, attributes it to the game’s “epic gunfights, impossible escape scenes and a plotline filled with betrayal.”

Even though the commercial shows precious little gameplay, you’re unlikely to see a more accurate pitch for a video game this year. “Uncharted 2” (rated T, $60 for PlayStation 3) is the best movie I’ve ever played. Boasting a blockbuster-worthy story, solid voice acting, spectacular explosions, crazy escapes and big-time shootouts, the game does a great job at making you feel like a cross between Indiana Jones, Rambo and “Tomb Raider’s” Lara Croft. But the same design decisions that yield some of the best dramatic pacing in video gaming also can make you feel like you’re an actor in someone else’s movie, not an empowered explorer out to uncover a lost city, best the bad guy and get the girl.

You play as Nathan Drake, a brainy, dreamy adventurer with a perpetual five o’clock shadow and half-tucked shirt. The game opens with a badly injured Drake hanging from a train car that’s dangling over a cliff. After escaping the train, just before it plunges over the precipice, Drake passes out in the snow and the story flashes back to Drake and two fellow treasure hunters’ deciding to seek out Marco Polo’s fleet of lost ships. The ultimate goal is the fabled, wish-granting Cintamani Stone.

Of course, it’d be a pretty boring game if you were the only one gunning for the stone, and it’s not long before one of your confidantes betrays you and goes to work for Zoran Lazarevic, a ruthless Serbian war criminal who believes the stone will give him the power to rule the world. Given that his heroes include Hitler, Stalin and Pol Pot, you have a small interest in getting the stone before he does.

Along the way, you’ll loot a museum in Istanbul, travel to Borneo in search of Polo’s ships, then head for a city in Nepal, the Himalayan wilderness and a Tibetan village, among other locales. Throughout your journey, your race against Lazarevic is palpable. Time and again, the Serbian’s private army corners you with helicopter gunships, tanks or entire platoons of soldiers. As a friend of mine pointed out, Drake hilariously transforms from a pacifist wary of harming museum guards to a guy who shoots down a helicopter in the middle of a crowded city with nary a thought of collateral damage.

But the game’s not all gunplay. As you traverse ruins and evade gunfire, you’ll be called upon to put Drake’s physical and mental fitness to good use, climbing buildings, leaping across chasms and solving fairly easy puzzles. If you get stuck, a contextual hint system will help you along.

All in all, the game’s top-notch visuals, terrific score, great voice acting and mythology-packed, race-the-tyrant plot make “Uncharted 2” the closest you’ll get to starring in an “Indiana Jones” movie. But the same design decisions that give the game its thrill-a-minute pacing can lead you to feel as if you’re walking down a set path. There’s usually only one route through the ruins, and one way to complete any objective. Explosions and other environmental hazards are always triggered when Drake reaches the same spots, and occur closely enough to create a sense of danger, but far enough away not to harm Drake. After a while, you learn not to flinch every time this happens. Dim-witted enemies behave consistently enough that it doesn’t take long to figure out which strategy the developers want you to take in any given battle.

None of this keeps “Uncharted 2” from becoming an essential title for any PS3 owner. Its 10- to 12-hour single-player game should be must-play material for any aspiring game designer seeking to learn a thing or two about narrative flow. And a robust slate of multiplayer options that includes an experience-based ranking system, deep, movie-making machinima toolset and the requisite deathmatch, team-based and humans-versus-the-AI modes will extend its shelf life.