Marv is turning 75, his party guests are about to arrive, his wife, Lois, is baking his favorite cake, but all he can think about are the galloping horses he keeps hearing whenever he's alone in the living room. That and the vivacious younger woman who keeps appearing to insist that the sofa is a Pontiac with a very loud engine, and that Marv is actually on a cross-country road trip instead of sitting around at home, waiting to acknowledge that he has finally grown old.

The Horses is written by playwright Brian Thorstenson (Over the Mountain, Shadow Crossing) the first-ever commissioned play by Marin County's innovative Alternative Theater Ensemble. The company, which presents professional productions never in theaters but always in temporary San Rafael storefronts, has earned a reputation for first-rate work done with an absence of frills. The new play is a fine example of that, a lyrically written comedy-drama-mystery-fantasy that defies categorization, alternately baffling and then charming its audience.

The story, which takes place over the course of a single day, at first seems to be that of a man having memories of a long-ago affair, then unfolds a little, asking us to consider that Marv (played by the masterful Will Marchetti) may be in the early stages of dementia. The other possibility, of course, is that Marv's experiences are real. There are others as well, each arising gently and gracefully from the previous. Those who prefer their art to make sense will find all of this unsettling, or at least confusing, but Thorstenson is the kind of writer who seeks the truth that simmers and lurks beneath the bare facts. The Horses, with the help of a sensational cast, manages to convey profound emotion in spite of its bold avoidance of literal reality.

Marchetti plays Marv with a blend of curmudgeonly irritation, youthful restlessness, childlike wonder and flat-out fear: fear of growing old, fear of losing his dreams and fear of death. As Lois, Marv's patient but increasingly concerned wife, Frances Lee McCain is equally good. McCain (film fans might recognize her as the mother in Gremlins—"Get out if my kitchen!") imbues Lois with her own kind of dignity.

The dialogue is rich, funny and rat-a-tat. Staged as it is in an empty retail space, the set consists of little more than the couch and a few paintings. Special mention should be given to Mark Robinson's excellent sound design, conjuring all of those stampeding horses as Thorstensen tells his lovely, sweet, gently off-the-wall tale. The Horses will not be everyone's cup of tea, but for those with Marv's spirit of adventure, it's a great big gulp of fresh air.

The Horses runs Thursday–Sunday through Nov. 15. Thursday–Saturday at 8pm; Sunday at 2pm. 1609 Fourth St. (corner of Fourth and G streets), San Rafael. $15–$25. 415.454.2787.

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