In a contest between a renowned overactor (Al Pacino) and two equally veteran underactors (Christopher Walken and Alan Arkin), who do you suppose will prevail? That’s a trick question, actually, as what happens to these three septuagenarian ex-mobsters in Stand Up Guys is never in doubt. Pacino’s Val is released from prison one morning after a stoic 28-year term, yet his vengeful old boss wants him dead. Walken’s Doc is the kindly, lonely codger who greets Val upon release, a .45 tucked in his waistband. Arkin is their widowed pal, barely kept alive by oxygen in an old folks’ home.What follows in this tame, fundamentally lazy comedy (call it the Best Exotic Marigold Mobster Hotel . . . or no, wait, simply OldFellas), are gold-hearted hookers, car theft, the snorting of stolen prescription drugs, reconciliation with lost kin, Viagra-induced priapism, and even the rescue of a damsel in distress. Most of the drama comes from the conflict between Walken’s alarmed thatch of hair and Pacino’s dark, stealthy rug; it’s a war of rival hairlines, like the moon tugging at the tides. Then comes the inevitable bullet-flying finale, a slo-mo send-off for our noble trio of off-white knights.”Let me talk for two fucking seconds!” demands Pacino, but talk is all he does. His leering at young female flesh uncomfortably recalls Scent of a Woman; only once or twice does he relax the bantam strut to slump in the booth of the hoods’ favorite diner, looking like an older, even more exhausted Donnie Brasco—and equally aware of his fate.The few pleasures here include Walken’s proudly high beltline (almost to the nipples), Julianna Margulies showing up as a nurse (just like E.R.), and English actress Lucy Punch in full Five Towns mode as a Jewish brothel owner who evidently stole Dustin Hoffman’s eyeglasses from Tootsie. Otherwise, director Fisher Stevens slogs through the pages of Noah Haidle’s mushy script.Which actor finally comes off best? Arkin, the guy with the least dialogue and screen time. In one exchange, he asks Pacino philosophically, “What makes you the arbiter of whose pants are important?” What indeed? Now there’s a scene I’d like to see expanded into a different movie: 100 minutes of Arkin, Pacino, and Walken talking about pants.bmiller@seattleweekly.com