“Based on a true story,” I heard from somewhere across the theater.

The familiar words had appeared on screen, and an elderly man had taken it upon himself to read them aloud, to the rest of a sizable audience seated for a matinee showing of the anti-child-trafficking thriller Sound of Freedom, starring Jim Caviezel. For the seasoned moviegoer, this phrase is a joke — we know that cinema will stretch almost any “truth” to the breaking point — and the rank insincerity of such a pronouncement is the foundation of the prankish opening titles of Fargo.