As the shortest kid in his seventh grade class in a Long Island school in the 1970s, Robert Montano yearned for a way to make himself bigger, perhaps even using his diminutive stature to his advantage. There’s nothing diminutive about Montano in his tour-de-force solo show Small, in which the veteran actor and dancer swaggers across the stage playing a multitude of characters while off-handedly addressing the audience with confident, look-at-me-now bravado.

While dancing was his first true love — a passion to which he’d return, with multiple stints on Broadway in the ’90s — he first tries to exploit his youthful smallness by becoming a jockey. With the blessing of his parents, an Italian American art professor at Pratt who drank a little and a church-going Puerto Rican saleswoman at a jewelry store who maxed out her credit cards, young Bobby starts working after school and in the summers at the Belmont race track, apprenticed to a jockey named Robert Pineda.

Montano does a skillful job embodying the various characters in the stables, from the fatherly Pineda to the prim Southern horse owner to the bow-legged hick of a trainer who punctuates his racial epithets with well-timed spits. His approach to female characters, like a stable hand in her early 20s who almost seduces Bobby until she learns he’s only 14, tilts more toward effeminate caricature. But he manages to draw us into a narrative that takes a much darker turn when he finally hits an adolescent growth spurt that makes it difficult to maintain a jockey’s weight — at least without resorting to bulimic purges (called “flipping” in the sport) or amphetamines (which he soon admits to popping like Chiclets).

The drama of Montano’s story is heightened by Jamie Roderick’s lighting design, which shifts in quick, cinematic cuts to reveal new slices of the barnlike set (by Christopher and Justin Swader) as well as Montano’s nimble and expressive body. Particularly effective is the underlighting of a metal grill on the stage’s raised platform to represent the “monster” scale that Montano repeatedly mounts for all-important weigh-in sessions that will determine whether or not he can actually compete. Director Jessi D. Hill builds tension in other ways, too, using Brian Ronan’s sound design to re-create the muffled announcer’s call of a race.

But the show’s greatest resource is Montano, who exploits his physicality to great effect — whether straining to drop pounds, crossing himself as his devout mother in prayer, or hunched over a thoroughbred visibly struggling to maintain control. Small lifts you into the saddle and challenges you to hang on for a bumpy but exhilarating ride. ★★★★☆

SMALL
Pershing Square Signature Center, Off Broadway
Running time: 1 hour, 45 minutes (no intermission)
Tickets on sale through July 25 for $49 to $114