Review: Don’t mistake “Sleepwalk With Me” as a story about a man coming to terms with the rare and intriguing REM sleep behavior disorder. Mike Birbiglia’s semi-autobiographical new film is a highly personal and often understated account of a struggling comedian in a troubled relationship. The sleep disorder gets little screen time, but those moments are memorable and pivotal to the story.

Birbiglia, a comedian and regular on the popular radio show This American Life, co-wrote, co-directed and stars as his thinly veiled doppelganger Matt Pandamiglio. Matt is a thirty-something who is facing not-so-subtle pressure from his long-time girlfriend and family to get married. He adores his girlfriend, who is played by Lauren Ambrose, but he just can’t bring himself to marry her. On top of that, his aspirations to become a stand-up comedian are going nowhere. He spends his evenings bartending at a comedy club, where he occasionally gets to perform.

Matt’s anxieties begin to bubble over into strange and vivid dreams, which he acts out in his bedroom. His father is quick to notice that he may have REM Sleep Behavior Disorder, a rare and dangerous parasomnia that gets worse over time.

Instead of seeing a doctor, Matt gets swept away by an opportunity to jump-start his comedy career. While he’s on the road, the sleep disorder causes a near-fatal accident, which happened to Birbiglia in real life. A dream about a missile attack caused him to jump out of a second-story window of a La Quinta Inn.

“Sleepwalk With Me” succeeds as a small independent release and as an introduction to a very serious sleep disorder. The movie tastefully mixes Birbiglia’s joke-laced narrative-driven approach to stand-up comedy with the modest, thoughtful storytelling of This American Life. This is no surprise: the film was produced and co-written by Ira Glass, the host and creator of This American Life.

The film provides a fairly realistic view of REM sleep behavior disorder, and the dream sequences involving the disorder are especially imaginative (see below). Also novel is the method in which the film explains REM sleep behavior disorder to the audience. Without spoiling anything, it involves a cameo by Dr. William Dement, the real-life father of sleep medicine. For this reason alone, “Sleepwalk With Me” is worth viewing for anyone with an interest in sleep medicine.

As bizarre as it sounds, REM sleep behavior disorder is a real sleep disorder. It is recognized by the International Classification of Sleep Disorders – Second Edition. People with REM sleep behavior disorder often flail, shout, punch, kick or leap as they act out their vivid dreams. The sleep disorder gets worse over time when left untreated, and injury is likely. In extreme cases, the dreamer may injure or kill themselves or a partner.

A board-certified sleep physician diagnoses REM sleep behavior disorder using an overnight sleep study. The disorder is treatable with medications such as Clonazepam combined with bedroom safety precautions. Birbiglia has stated before that he confines himself in a sleeping bag while wearing mittens, so he doesn’t injure himself as he sleeps. People with REM sleep behavior disorder should also move any objects away from the bed, and block any windows.

Sleepwalk With Me opens on August 24, and is showing in a limited run at these theaters.