For rare indeed is the musical that burrows as deeply into one character's head as this one does, without losing sight of either his humanity or theatricality, and any method able to accomplish that should be fair game. Rasbury hasn't so much composed the show as "soundscaped" it by blending traditional-style instrument sounds with blaring TVs, ringing telephones, garden implements, and toys. This approximates not only the devastatingly impossible experience of Max, a very young boy living with autism (the stunning Marlon Sherman), but also that of the parents (Michael Winther and Mary Mossberg) who truly can't understand what he's going through.

This cacophony, which also includes the highly fragmentary songs themselves (for which both librettist Carlin and Rasbury provided the minimal, but maximally invasive, lyrics), wrenches us right into Max's ever-meandering mind. He perceives the world as little more than a series of broad, endlessly repeatable strokes that don't so much communicate as pollute what is for him a satisfyingly simple worldview. He may not understand basic questions, or be able to form many original and varied sentences, but he makes his needs, demands, desires known nonetheless.

One movie, and one movie alone is allowed on television: The Wizard of Oz (though occasional forays into Brian Williams's Sesame Street episode or a certain miracle-weight-loss-product commercial are allowed). Something about the Millard Fillmore entry in his electronic game about the presidents - all of whom he's memorized - entrances him to no end. Breakfast is always and only waffles. When Max's parents try to dress him, he'll rip off his shirt and shout "Abercrombie!" And power lines hold for him a strange obsession, as though his entire being were somehow wrapped in the energy they transfer.

For his well-being, his parents are determined he never leave the house. But one day he steals off into the world, and finds it filled with strange creatures. There's a woman in a wheelchair (Ali Stroker), and a highly interested next-door neighbor (Everett Quinton) with a leaf blower. A pegasus (Tricia Burns) - resembling one of Max's favorite toys - soars over the clotheslines and encourages him to dream. When Max wanders near a dumpster, he finds a rapper inside who can't stop rhyming about Mount Rushmore.

To say things never move beyond this story is both true and misleading. The action ends when Max reunites with his parents, in whatever final condition, but this is not a show that needs plot to speak volumes about the people it follows. Max is an amazingly well-rounded creation, from the first scene ("Noise Symphony") when he wakes up to the violent layering of sounds he can't escape through the end of his picaresque journey. Mom and Dad's entire marriage is summed up in seconds, as their constant braying of the words "stuck" and "fried" proves they're just as trapped in themselves as their son is. One song, which consists of only the words "This Is Normal" repeated over and over, is one of the year's most gorgeous and heartrending, as much for its haunting and soaring melody as the various implications and contradictions its singers bring to its lyrics.

Director David Schweizer flawlessly marshals everyday staging techniques to eye-popping effect, whether "flying" the pegasus or summoning up an impromptu presidential fashion show. Caleb Wertenbaker's sets - including precariously arching ropes for the power lines - and Justin Townsend's lights give the low-budget production an unbelievably opulent feel. With the exception of Quinton, who was terrific in Devil Boys From Beyond at the Fringe Festival this summer but here minces and cloys to little effect, the performers are outstanding in conjuring people who precariously exist both inside and outside of Max's head. As for Max himself, Sherman captures every conceivable note of the wonder and confusion the boy is enduring. The look on his face - part tortured, part amazed, part jubilant - as he tries to absorb the myriad insoluble aural elements of the world around him, is perhaps the most unforgettable port of this tiny but masterful performance.

Sherman's expressions relate all the bemusement, horror, and silent hope of a victim of his own mind far better than the something like the bombastic and inconsistent tone musicals usually take to suggest at mental instability (Next to Normal being the highest-profile current example). But they're ultimately only one component of a larger, more compelling whole that uses unique audio techniques to define the borders of an existence most of us can't even imagine. For Max, they might sound like a wall of largely incomprehensible noise. But as part of the complete package of Max Understood, they may as well be a grand symphony.

Max Understood
Tickets online and current Performance Schedule: The New York Musical Theatre Festival