Mildred Hayes, a hard-nosed mother is seeking justice for her murdered daughter. With no arrests after seven months, Mildred puts up three roadside signs to goad Ebbing police chief into action. But the law - and especially Sam Rockwell's hot-headed deputy - don't take kindly to the provocation. And the townsfolk are on their side. But Mildred doesn't care about ruffling a few feathers. In fact, she's happy to pluck the whole bird.