In a climactic scene in “Howie the Rookie,” the violence reaches an awful pitch. Two men, caught in a berserker rage, snap and rip at each other like fighting dogs. Averted eyes won’t help, though; there’s nothing to look away from. Mark O’Rowe’s play consists of two monologues, back to back. That scene of physical brutality exists entirely in our imaginations, called up in vivid detail by the Rookie himself.

Mr. O’Rowe also wrote the recent film “Intermission,” with which “Howie the Rookie” shares a certain continuity of theme. Again, Mr. O’Rowe talks about the grittiest bits of south Dublin, populated with working-class lads who aren’t working. And both pieces – one a film, one a play – have that wandering eye that notices the way two lives can overlap and eventually interweave. Mr. O’Rowe’s unlikely strategy – two narrators who never share the stage – doesn’t need a camera to be cinematic.

First we meet Howie Lee, a bruiser with a soft center. His favorite activity is “getting after” people, which can mean anything from a leisurely chase down an alley to a savage beating. When Howie and his mates decide that their pretty-boy chum the Rookie passed along a savage infestation of scabies, the night’s mission becomes to punish him. By the end of the first act, unexpected tragedy has already struck. In the second act, when the Rookie arrives to tell us his side of the story, we find the men descending into ever further depths of humiliation and destruction.

As played by Mark Byrne, Howie has a perennially bright outlook. Things that strike us as grotesque he greets with a sunny “Nice!” and an endearing smile. His sweetness floats right on the surface, and it seems hard to imagine him as the group’s go-to thug.

He’s dear, but director Nancy Malone seems to have cautioned Mr. Byrne to speak slowly so his accent and Irish slang won’t catch an audience flat. Unfortunately, the adrenalized first act suffers for it. Our lad prides himself on his tackling ability – Mr. Byrne should have tackled the text as well.

John O’Callaghan as the Rookie, though, has been perfectly cast. Scenes of ridiculous physical comedy (Howie’s dance with the portly, ski panted “Avalanche,” the Rookie’s unhelpful flatulence in times of crisis) keep our minds off the tragedy we know is coming.

Navigating between two extremes, Mr. O’Rowe’s play needs someone with Mr. O’Callaghan’s impressive narrative control and gorgeous comic timing. He simpers and quails and runs away, slipping in his boots on the stage-floor. He keeps us just as off-balance as his tractionless boots, and when the fall finally comes, it’s exhilarating.

***

Out of a smoky haze, as a guitar wails and flames lick the doorway, a man leaps onto the stage. He’s tuxedoed, dangerous, a rock ‘n’ roll screamer – and he’s a clown. A little forelock of red and yellow licks out of his forehead, his eyebrows scroll calligraphically, and it looks as though he’s rouged his ears.

For the edgiest of the hip-hop crowd, or for those who remember KISS with any fondness, clowns and loud music aren’t necessarily mutually exclusive. But this guy isn’t just in whiteface. He has a tricycle, a brace of puppets, and no trouble doing half the show in his bunny slippers.

In “Uncle Jimmy’s Dirty Basement,” Uncle Jimmy (James Godwin) and his band forge bravely into new puppet-rock territory. Taboos written long ago, like “Never use your own cat in a rock montage” or “Try not to smell the audience’s feet” crumple and die before their onslaught. Sense and logic also wither on the vine in Uncle Jimmy’s basement, but for most of the evening no one will miss them.

Uncle Jimmy and friends have long been a fixture in venues like the Bowery Poetry Club. The screeching audience occasionally sings along, greeting old favorites with yowls of appreciation. The show can stretch to two hours, which will feel long, especially during certain bits with a puppet sidekick named Chuck-Bob. But once Uncle Jimmy starts singing again, or wandering into the audience, or stripping, you won’t want to leave the basement.

“Howie the Rookie” (553 W. 51st Street, between Tenth and Eleventh Avenues, 212-757-3318).

“Uncle Jimmy’s Dirty Basement” until May 29 (150 First Avenue, between 9th and 10th Streets, 212-477-5288).