剧情围绕巴尔的摩警察局的一群凶杀案调查小组的侦探人员展开，深入描述了警察局探员细致入微、抽丝剥茧的探案过程。与其他同类电视剧不同的是，该剧非常强调真实性，几乎所有的细节都建立在实际探案的基础上。

Nan Moore is a U.S. government employee whose son is killed when Korean Air Flight 007 is shot down by Soviets on September 1, 1983. While the "official" story maintains that the flight accidentally veered too far into Soviet territory, was mistaken as a spy plane and shot down when it failed to identify itself, Ms. Moore suspects otherwise. However, in the course of her struggles to get to the bottom of what actually happened, she finds herself constantly stonewalled. Facing a conspiracy of silence and the increasing hostility of the authorities, Ms. Moore attempts to find out exactly what occurred, but with every answer she discovers, new questions arise...