After her mother is murdered on Halloween, a rebellious teenager travels back in time to 1987 where she must stop the young would-be-killer and get back to her rightful time line before she's trapped in the past forever.
1900年，在美国旧金山唐人街，华裔印第安猎人阿鬼（王宝强 饰）与留美青年秦福（刘昊然 饰）因一场凶杀案偶然结识，误打误撞组成“唐人街神探”组合。开启了一场笑闹探案之旅……
一天，龙一从阿飞那里得知他（龙一）价值五百万的字钱被独眼龙给抢走了。龙一知道后赶紧去追讨。当他打败独眼龙时。却发现这一切都是阿飞给他设的局。然后，他和独眼龙也给阿飞设了个局。最后，龙一打败阿飞追回了自己的字钱。
