The sound design and lead performance in Sound of Metal are so good that it’s easy to overlook its spotty screenplay and pedestrian filmmaking.

Foremost a showcase for Riz Ahmed, who more than rises to the challenge of playing Ruben, a hard rock drummer who loses his hearing, the feature directorial debut of The Place Beyond the Pines co-writer Darius Marder shows plenty of promise early on, though never with a sense of style he can call his own.

The rapport between Ahmed and Olivia Cooke (sporting strange bleached eyebrows) as Lou, Ruben’s lover and vocalist partner in the duo Blackgammon, is strong onstage and inside their Airstream home, and incredible tension arises when Ruben suddenly develops a muffled noise in his ears, the first of sound designer Nicolas Becker’s brilliant contributions that put viewers in Ruben’s confused head.

Ruben’s frantic rush to save his hearing — and in turn his livelihood and more — is wrenching to endure, especially an auditory test that he fails miserably, and his confidence that he'll get an expensive cochlear implant teems with painful misguidance.

With the conflict built up so well, the narrative frustratingly starts to fall apart once Lou, with help from a mysterious friend, arranges for Ruben to receive help at a facility for deaf people run by Vietnam veteran Joe (character actor Paul Raci, in a breakout role), then just as quickly bolts to abide by its restrictive but allegedly necessary rules.

In getting Ruben to the facility and revealing why it’s a good fit — he’s been sober for four years and his deaf brethren there are fellow addicts — Marder and his co-writer/brother Abraham (who also composed the film’s music with Becker) dole out information in bread-crumb fashion, obscuring far too many crucial details.

While Ahmed excels at conveying the alienation of being in a new place, unable to properly communicate, as well as the infectious joy of Ruben learning how to sign and become part of the community, the script’s numerous holes gradually drag it down. From Lou’s lack of development despite her actions significantly impacting Ruben’s life to his ultimate decision regarding the implants, so much could have felt plausible with one or two lines of dialogue, yet they go unspoken.

Though the dread of waiting for something bad to inevitably happen compensates for some of those gaps and the final scene is rather poetic, these last-ditch efforts can’t quite save Sound of Metal from its prior missteps, which nevertheless seem destined to inflict viewers with amnesia surrounding these shortcomings.

Grade: C-plus. Rated R. Available to stream via Amazon Prime Video

(Photo: Amazon Studios)