Jackie Chan, known for doing his own punishing stunt work, finds the perfect foil/costar in Johnny Knoxville, a proven Jackass who has taken more than a few lumps for his own, um, art. Plot-wise, this is the same movie Chan’s been making for years. Hong Kong cop seeking his revered partner’s murderer teams up with a sleazy American gambler who could (be forced to) help him. The main fun in this cheerfully dopey retread is wondering which truly perilous stunt they get up to next. But it’s lively and diverting, and the lush scenery may boost Chinese tourism. Loved the Mongolian sequences. Adele? (107 min)