Birbiglia -- who enters and exits through a gaping space deliberately designed by Beowulf Borrit as a metaphor for a crucial turning-point in his past -- is never explicit about the lesson he's teaching and which he earned the hard way. But put into words, it would go something like, "See your doctor at the first sign of significant physical or psychological trouble." Apparently, some years ago, the comedian began having dreams that propelled him from his bed onto dizzying surfaces like the top of a bookshelf or through a shattered hotel window and towards a bloody visit to an emergency ward. While Birbiglia ultimately takes serious aim at the perils of denial, he keeps uppermost the many yuks in the basically frightening story he's telling.
Birbiglia only hints at the psychic reasons for what he and his attending physicians eventually diagnose as "REM sleep disorder" and these days require him to nod off nightly in a sleeping-bag. He only implies that seeing nightmarish objects like jackals and launch missiles careering towards him is linked to disturbing waking events like the misgivings he had at the prospects of marrying his first long-time girlfriend.
To look at Birbiglia is not to see someone blatantly in the dumps, but he does count on his innate awkwardness to charm audiences. Wearing running shoes, baggy trousers, and a shapeless pullover with sleeves that droop two inches below his wrists, he practically says "Mother me" to women and alerts men he'll be no competition in the next girl-hunt.
While Birbiglia's appearance may be somewhat calculated, his basic appeal as a performer is that he's calculated in no other way. His comedy is based on the truth of his life and the truth of his mind's quirky turns. As he digresses to talk about turning off cell phones, his slow sexual development, his cautious father and gregarious mother, his hypochondria, an actual cancerous tumor in the bladder caught in time and other subjects that could be called ephemeral, he recalls Woody Allen's nebbishy persona, Steven Wright's cerebral musings, and even the manner in which Sam Levenson giggled at his own jokes.
I wouldn't sleepwalk with Birbiglia through a hotel window; but, having seen this show, I would gladly follow him everywhere else.