DATONG follows the life and work of a controversial Chinese Communist Mayor GENG YANBO to tell the story about how he takes a radical reform to demolish 140,000 households and relocate half a million people to give way to restoration of Ancient relic walls in order to adopt a clean economic growth from tourism and culture, which he believes will do good to DA TONG citizen in the long term. With two years in the footsteps of GENG, along with the changing ideology and confrontations from the public, the film is trying to draw a looming shape of future of China.

七年前的婚礼上，许三娜（阎妮 饰）的父亲，伍波（耿乐 饰）的准岳父实在看不上将来的女婿竟是一个一文不名的穷光蛋，大婚当天伍波落荒而逃，婚礼现场留下了目瞪口呆的亲朋和傻掉的新娘。逃婚后伍波立下宏愿，一定在短时期内创业成功，挣大钱住豪宅，让羞辱过自己的人看看，怎奈商场如战场，几年打拼下来，钱没赚到反而负债累累，走到了濒临自杀的地步。回过头来看三娜，当初伍波逃婚令她蒙羞，她发誓一定要嫁入豪门，但七年过后，高不成低不就的三娜仍待在闺中，成了年逾三旬的剩女。 七年后，当初的冤家竟莫名做了邻居......