Movies incorporate plot twists all the time, but rarely with the mind-blowing relish of “Cold In July.”

A noir thriller by Jim Mickle (“We Are What We Are”) that begins as a tight drama about two fathers engaging in a war of nerves, this unpredictable and ultimately stunning film hits the brakes halfway through with the dazzling arrival of Don Johnson in a red Cadillac.

From there, both the car and “Cold in July” take a sharp left from smart pulp to far darker and heartbreaking tragedy, headlights trained on real evil, guilt and nobility.

Before that happens, the story centers on the shooting of an intruder in the home of family man Richard (Michael C. Hall). Richard, an otherwise peaceful businessman in a small Texas town, appears to have killed a seasoned felon just before the latter’s father’s release from a nearby prison.

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When that scary second father, Russel (Sam Shepard), turns up seeking revenge, Richard begins to see larger forces and deceit at work.

Johnson’s Jim Bob — a tough but twinkling private detective — is enlisted to uncover the truth, leading to a showdown in what feels like a border town between hell and destiny.

Shepard and Johnson have never been better, but Hall is particularly brilliant capturing an uncertain character coming to life in a dangerous cause. When his Richard staggers up from the floor during a climactic battle, you can see in his eyes a new kind of knowledge of the world — and a readiness.

Tom Keogh: