A ripe mound of earth, festering with sickly flowers and garbage, rises from the upstairs stage of the Flea Theater these days. Audience members in the front row for “Wolf in the River” — which opened on Monday night in a highly intimate in-the-round production — could easily lean over and rub their faces in the muck, which may well be the symbolic intention of this play’s creator, Adam Rapp.  But mostly, this squalid pile exists as a place for an enthusiastic tribe of young theater folk — members of the Bats, the Flea’s resident acting company — to get dirty, histrionic and, on occasion, naked. It must be said that they seem to be having just as good a time doing so as Mr. Rapp apparently had writing and directing this tall and bloated tale of nasty doings on the banks of a cannibalistic river.  Just so you know, we, the audience, are that river (as we’re told early on). In the world of Mr. Rapp, everybody gets to be a metaphor.  Mr. Rapp, whose “Red Light Winter” was a finalist for the Pulitzer Prize for drama, is an uncommonly prolific and profuse playwright who wallows shamelessly and happily in excess. No bare-bones minimalism for this advocate of all things purple and lurid, who apparently never met a poetic image or theatrical shock tactic he couldn’t find a use for.  Most of his work involves disaffected and dysfunctional Americans perpetrating gory acts of violence upon one another in environments that embrace both blighted urban apartments and affluent suburban homes. For “Wolf in the River,” he has ventured into Dogpatch territory, where — it may surprise you to learn — disaffected and dysfunctional Americans perpetrate gory acts of violence upon one another.  This particular group of feral young things belongs to an indigent tribe ruled by the tyrannical and sadistic Monty Mae Maloney (Xanthe Paige), a woman with a smokin’ body and Beyoncé moves. Monty, who keeps the members of her clan solvent by selling their plasma to blood banks, wields a crocodile-headed cane to squelch any signs of rebellion.  Pity, then, poor li’l Tana Weed (a very good, very brave Kate Thulin), a wistful 16-year-old with dreams of crossing the river that keeps her from her true love, Debo (Maki Borden), a skiff-riding swain with a passion for old cars. She can’t expect any assistance from her brother, Dothan (William Apps), a veteran who returned mute and deranged from the war in Afghanistan, where he committed unspeakable atrocities.  Filling out the surrogate family portrait are Aikin (Karen Eilbacher), Monty’s trusted right hand, who eats the fantastical, senses-numbing flowers that grow in abundance, and the simple-minded Pin (Mike Swift), first seen copulating with a blowup sex doll.  A scene from Adam Rapp’s play at the Flea Theater.  Tana’s story is narrated and annotated by the bare-chested Man (Jack Ellis), also known as the Wolf, who occasionally takes on the role of Monty’s sedentary mama, Dumptruck Lorna. The Man is prone to flights of savage lyricism. A typical example: “The moon is a sickled leopard’s tooth pinned to obsidian, its light silvering the violent undulations scoring the skin of your unforgiving water.”  Or, if you prefer a folksier approach: “Time is a tricky old sow, ain’t she?” Or Aikin’s description of swimming in the river: “The drum fish was drummin’, and the catfish had they hackles up, and them cottonmouths was slitherin’ with the quickness.” It is easy to imagine “Wolf” as a collaboration between Tennessee Williams and Erskine Caldwell, both deep in their cups.  The artery-clogging prose is enlivened by the vivacious staging, which makes fecund use of Arnulfo Maldonado’s set. (Michael Hili and Hallie Elizabeth Newton did the barely there, recycled-looking costumes, and Masha Tsimring, the creepy lighting.)  The ensemble, which includes a backup group called the Lost Choir that roams the audience like the walking dead in search of brains, periodically breaks into haunting bucolic song or choral sighs and whispers. Ms. Paige’s wicked Monty leads a pop-siren production number that suggests a down-market variation on a Super Bowl halftime show.  The production also makes dexterous and multifarious use of Monty’s cane, a derelict refrigerator and, for the climax, a thick suspended rope. Warning: The cast members will be very much in your midst throughout, sharing their glee at the chance to act up a hillbilly storm beneath that ol’ sickled leopard’s-tooth moon.  Category Off Off Broadway, Drama, Play  Credits Written and directed by Adam Rapp  Closing Date May 2, 2016  This information was last updated: Feb. 1, 2016  Wolf in the RiverWritten and directed by Adam Rapp; additional text by the Bats; sets by Arnulfo Maldonado; lighting by Masha Tsimring; costumes by Michael Hili and Hallie Elizabeth Newton; sound by Brendan Connelly and Lee Kinney; props by Zach Serafin; fight choreography by J. David Brimmer; aerial consultant, Sarah East Johnson; assistant scenic design, Anshuman Bhatia; assistant lighting design, Becky Heisler; assistant director, Anne Cecelia Haney; stage manager, Morgan Leigh Beach. Presented by the Flea Theater, Niegel Smith, artistic director; Carol Ostrow, producing director. Through May 2 at the Flea Theater, 41 White Street, Manhattan; 212-352-3101, theflea­.org. Running time: 1 hour 45 minutes.­WITH: William Apps (Dothan), Maki Borden (Debo), Karen Eilbacher (Aikin), Jack Ellis (the Man), Xanthe Paige (Monty), Mike Swift (Pin), Kate Thulin (Tana) and Alexandra Curran, Jack Horton Gilbert, John Paul Harkins, Artem Kreimer, Derek Christopher Murphy and Casey Wortmann (Lost Choir).  A version of this review appears in print on March 22, 2016, on page C1 of the New York edition with the headline: Amid the Young and the Ruthless. Order Reprints| Today's Paper|Subscribe
This new play, performed by the Bats, the Flea Theater’s resident company, centers on a wistful 16-year-old surrounded by a feral and violent clan.