Mariko, just like every winsome princess trapped against her will in a castle, longs to be rescued. But being rescued isn't her only longing. There is, of course, the delicate matter of the rescuer.
Salvation is all well and good, but the specifics of the saviour are just as important. Who's the face behind the silhouette in the doorway; what's the torso beneath the shirt? A/S/L? Oh, there'll be smiles and grateful flutters of eyelashes no matter who topples the guard and bursts triumphant into the bedroom, but the man (or woman) should match the moment. Anyone else - unmentionably, unthinkably - might bring disappointment as well as freedom.
'Rescue the princess' is a premise as old as video-game time; at least as old as Karateka, a game originally released in 1984 when its maker, Prince of Persia creator Jordan Mechner, was a student at Yale University. But Karateka plays with the premise in a way few of its descendants have dared - ensuring this remake still feels unfamiliar some 30 years later.