Kung Fu Hustle (2004)

When the hapless Sing (Stephen Chow) and his dim-witted pal, Bone (Feng Xiaogang), try to scam the residents of Pig Sty Alley into thinking they're members of the dreaded Axe Gang, the real gangsters descend on this Shanghai slum to restore their fearsome reputation. What gang leader Brother Sum (Chan Kwok-kwan) doesn't know is that three legendary retired kung fu masters (Yu Xing, Dong Zhihua, Chiu Chi-ling) live anonymously in this decrepit neighborhood and don't take kindly to interlopers.