A jarring lead performance anchors Thunder Road, given by Jim Cummings, who is also the film’s writer and director. As Jim Arnaud, a well-meaning police officer who just can’t get out of his own way, he’s like Napoleon Dynamite with a bit more self-awareness. Or maybe Barney Fife with Tourette syndrome. Delivering a eulogy at his mother’s funeral, Jim intends to perform a dance routine in uniform to Bruce Springsteen’s “Thunder Road,” and when the child’s boombox he’s brought fails him, he forges ahead anyway without any music. That’s followed by a stream-of-consciousness speech which veers back and forth between sobbing tears and steely stares—and a random reference to John Wayne for good measure. Cummings manages this tightrope all film long (he has at least three other mesmerizingly cringy monologues), never allowing Jim to become a simple joke. You genuinely feel for the guy, because it’s clear that his social awkwardness causes him real pain. As a narrative, Thunder Road doesn’t entirely cohere—various plot strands involve Jim’s ex-wife, his daughter, and his partner on the force—yet Cummings remains riveting, never letting you get an easy fix on this troubled, troubling character.