Last suppers are fraught by their nature, but Art “Crazy Train” Sligo has put himself together a doozy.

Art, a lifer from the dingier circles of professional wrestling, spends the entirety of “American Sligo” in a cherry-red unitard that stretches ominously over his considerable belly. The mullet wig stays off for most of the meal, his last before hanging up his various title belts, but he keeps it close at hand. And while he would just as soon wolf down his lamb and lima beans in silence, he’s not above laying down a Colombian Crucifix or the Flying Clothesline of Death on a family member if necessary.

So goes the latest exercise in painstakingly assembled chaos by the maniacally prolific playwright Adam Rapp.

Mr. Rapp, who writes plays in roughly the time it takes you or me to watch them, stays resolutely within his comfort zone — or perhaps his discomfort zone — this time out. “Sligo” lacks the personal aftershocks that pervaded his “Red Light Winter” or the apocalyptic whimsy that torpedoed his “Essential Self Defense.” Instead, he has returned to the fractured family dynamics that punctuated such earlier works as “Nocturne” and “Stone Cold Dead Serious.” (“Earlier” might be an odd term for a playwright whose first New York success came just six years ago, if not for the fact that he has amassed a corpus since then that equals those of William Inge and Lillian Hellman combined.)

In a slight deviation from his usual full-immersion style, Mr. Rapp, who also directed this production, has provided the audience with a fellow sufferer in the person of Bobby Bibby (Matthew Stadelmann), the “winner” of a seat at the table for this nightmarish meal. (He spent well over $1,200 in contest entries to land this honor, which then required a three-day bus ride to this remote corner of Ohio.) Everyone is already seated for dinner as “American Sligo” begins, and Bobby would be instantly recognizable even without the “I won the crazy train sweepstakes!” T-shirt. He’s about one-third the size of everyone else at the table, for one thing, and he’s also the only one whose eyes are in a perpetual bugged-out state of awe, terror, and/or discomfort.

The last emotion stems largely from the dithering torrent of questions, anecdotes, and general lunacy pouring from the mouth of Art’s sister-in-law, Aunt Bobbie (Marylouise Burke). Art and his hirsute, underachieving son Kyle (Michael Chernus) endure Bobbie’s prattle, for the most part, although a particularly inane story of hers prompts Art to decree a 90-second period of silence.

The muted hostility and barely concealed resentments are a mere prelude, however, to the arrival of Art’s other son, Victor (Paul Sparks), a cocaine-addled diabetic fresh from a stint at the penitentiary. (His crime involved the local Army recruiting office and, in Bobbie’s memorable phrase, “several pounds of his own feces.”) Once he arrives, followed shortly by the beleaguered girlfriends of both Sligo boys, considerable doubt arises as to whether “Crazy Train” will even make it to his bout with Kadhim the Syrian Desert Bull.

Perhaps fueled by Mr. Sparks’s blistering performance, Mr. Rapp allows the plot to slide into the sociopathic territory of Irish shockster Martin McDonagh. Mr. Rapp is hardly known for his chipper endings, but the emotions generated by Guy’s final match, the sizable amount of cocaine ingested by Victor, and the presence of three outsiders push his work to new levels of oddball nihilism. While past attempts at directing his own productions have led to a drift in both pacing and characterization, something about the Sligos has induced him to keep a tighter rein on his aggrieved wit.

One advantage to Mr. Rapp’s absurd fecundity is that a small but remarkable group of actors have honed his robustly verbal style to near perfection. Messrs. Boyd, Sparks, Chernus, and Stadelmann tackle his filigreed language with a second-skin poise that hearkens back to such playwright-driven companies as Odets’s Group Theatre or Brecht’s Berliner Ensemble. And the inexhaustible Ms. Burke joins their ranks with Aunt Bobbie’s dizzying array of seemingly aimless blather, which is actually a futile attempt at keeping the family’s animosities from boiling over. (That enforced lull in the conversation is a 90-second symphony of jitters and frenzied glances.)

The flip side to this familiarity is that “American Sligo” offers little in the way of surprises to anyone familiar with Mr. Rapp’s work. Wounded lowlifes will converse with a funky blend of erudition and demotic rage, secrete fluids (phlegm, vomit, and a post-Heimlich-maneuver mass of food in addition to those pounds of feces), and commit terrible, squalid acts leavened with the occasional poignant reminder of just how far they’ve sunk.

Even if “American Sligo” only intermittently achieves the gut-punch pathos that invigorated works like “Nocturne” or “Blackbird,” Mr. Rapp may be inching closer to molding his own penchant for scatological showmanship to the existential ache that makes even the likes of the Sligos recognizable. Such a combination may not be a Colombian Crucifix, but it will prove every bit as devastating if and when he gets it down.

Until October 14 (224 Waverly Place, between Seventh Avenue and Perry Street, 212-868-4444).