"Sometimes you don't gotta be a rocket scientist. You just need a rocket..." Thus drawls RZA in this Americanised reboot of writer-producer Luc Besson's 2004 Euro hit District B 13, which moves the action from paranoid Paris to dystopian Detroit. Athletic David Belle (looking more like a buff version of Daniel Auteuil every day) reprises the runny-jumpy "parkour" paradiddles that put such a spring in the original, while the late Paul Walker handles the punchy-drivey chores at which he excelled in The Fast and the Furious franchise. It's solidly unsurprising (and often quite boring) generic fare, spiced up with steroidal pectorals and fetishy catfights. The extraordinary leaping remains the main reason to watch, but the endless shooting, crashing and overacting takes the shine off the more bouncy pleasures.