查小刀（孙俪 饰）智商极高，但性格软弱怕事，莫非里（邓超 饰）不过是一介混混，但个性嚣张跋扈，一场车祸让两人相遇，莫非里毫无意外的狠狠在查小刀的身上诈了一笔。亲情淡漠，工作受挫，又遭恶人欺压，查小刀心灰意冷，无意之中得知了有一位名为折耳根（梁超 饰）的神医专治各种疑难杂症，于是便起了向他寻求良方的念头。 让查小刀没有想到的是，莫非里居然也是折耳根的病人，常年的失眠困扰着他令他痛不欲生。折耳根告诉两人，他们其实正是彼此的“良药”，为了“治病”，查小刀和莫非里结为搭档共同进退，惹出了无数的麻烦和笑话，与此同时，亦结下了深厚的感情。

高智商學霸與魯莽惡棍意外聯手當起討債夥伴，踏上爆笑不斷又麻煩滿點的公路之旅。

Adapted from the famous stage play of the same name, Devil And Angel (E Gun Tian Shi) follows Zha, played by Sun Li, a top student with a high IQ, who goes on a journey with Mo, played by famous Chinese comedy actor Deng Chao, a professional debt-collector and sometime hooligan, in order to face down her own neurosis, as well as cure Mo of his extreme insomnia.