Which is to say that Jake Gyllenhaal as the doughty Prince Dastan is just the latest in a long line of earnest, tunic-clad sides of beef. In fact, his potted British accent — this is ancient Persia, after all — can stand with Tony Curtis’s Bronx yawp in 1951’s “The Prince Who Was a Thief’’ for sheer what-the-hell period absurdity. But to expect more from a movie that doesn’t even take itself very seriously is probably a mistake.
For one thing, “Prince of Persia’’ has been stitched together from so many other movies that it plays like an attack of multiple déjà vu. Stray bits of “Star Wars,’’ “Pirates of the Caribbean,’’ “Crouching Tiger, Hidden Dragon,’’ and “Robin Hood’’ pass by like flotsam, and the overwhelming tone is good-natured but alarmingly generic. You’ve seen “Lord of the Rings’’? Here’s the CVS brand.
Dastan is the adopted son of Sharaman (Ronald Pickup), king of Persia, and please don’t spoil things by referring to the country’s modern name (shhh, it’s Iran). A former street urchin, he’s now a kind-hearted sort given to bare-knuckles bouts with his soldiers while the king’s natural sons Tus (Richard Coyle) and Garsiv (Toby Kebbell) busy themselves with expanding the empire. (Those names! They sound like the whims of a desperate Scrabble player; you keep expecting a consul named Etaoin Shrdlu to turn up.)
Off in the corner plotting evil deeds is the king’s brother, Nizam. Ben Kingsley appears to have researched this role by studying Max Von Sydow’s hambone Ming the Merciless in 1980’s “Flash Gordon,’’ and, truthfully, that’s probably the only sane approach. Nizam engineers a coup and pins the blame on Dastan, who hits the road with only a comely virgin priestess named Tamina (Gemma Arterton) and her glowing dagger for company.