Review: ‘Lost Transmissions’ ’ tale of mental illness in the music business fails to engage

A schizophrenic music producer and an introverted, aspiring songwriter on antidepressants form a tender bond in soul-crushing Los Angeles, courtesy of “Lost Transmissions,” a well-intentioned but frustratingly unengaging first feature by Katharine O’Brien.

After hitting it off at a gathering of mutual friends, mousy Hannah (intriguing U.K. actress Juno Temple affecting a nasal American accent and a wispy Lana Del Rey singing style) and British recording industry whiz Theo (Simon Pegg) would appear destined to make beautiful music together.

But if this sounds like the makings of another “Once,” no such luck.

It turns out Theo has a history of mental issues triggered by a lot of bad drugs he took during his wild rocker days, and when he goes off his meds he goes on tangents about time travel and hearing messages under radio static, resulting in the mad genius being committed against his will to a psychiatric institution.

Although both Pegg, famous for his lighter work in Edgar Wright’s sci-fi comedies, and Temple are impressively immersed in their respective lost souls, O’Brien, whose painstakingly naturalistic portrait of mental illness is based on a real-life relationship, demands viewer sympathy without sufficiently earning it.

Despite its penetrating handheld camerawork (by Arnau Valls Colomer) and mind-altering sound design, “Lost Transmissions” never quite manages to tune out the lingering element of self-indulgence.