What do a change purse made from human genitals, a box-cutter, and Churchill’s stogie all have in common? Well, they all fit neatly in a pocket. But according to Darren Murphy’s “Tabloid Caligula,” they are indispensable symbols of power – the sort of accessory that lets a person enter a room and dominate it without ever saying a word. Of course his characters haven’t made it quite that far up the ladder yet. In a scrubby little basement storeroom, three mean eyed types scrabble for the upper rungs by talking, reminiscing, and occasionally invoking the spirit of Alexander the Great.

Everybody likes a glimpse of a seedy underbelly now and then, and the hippest underbelly du jour belongs to the British petty criminal. In movies like “Layer Cake” and “Unleashed,” or ones featuring steamy Clive Owen turning up his collar, the London underworld has never seemed so attractive. Macho, lawless, and casually violent, it attracts budding Mamets or Tarantinos – all looking for a new way to poeticize the blood. The alluring-criminal genre has been around for a long time, but instead of harking back to Prohibition, or maybe the Wild West, Mr. Murphy takes us all the way back to ancient times to draw his parallels.

Part-time thug and wannabe carpet dealer Robert (Peter Tate) may have his headquarters in a tailor’s basement, but he is confident that the situation is temporary. Maps and plans for domination have started to spread over the walls, and his acolyte Joe (Chris Harper) can already picture the two of them as the lords of London’s Soho. Some desultory efforts are made about the rugs, but Joe and Robert clearly have their hearts in “the hurting business.” Robert’s imperial purple tie announces his pretensions to authority, so the work consists largely of Joe administering commissioned beatings. “He’s … keen,” cautions Robert to a client, before showing her Polaroids of some poor bugger’s destroyed face.

Joe may be keen – he’s almost lyrical in his descriptions of violence – but he’s not swift. Mr. Harper’s cheeks are always high with color, perhaps with embarrassment over idiot Joe’s many shortcomings. Robert, convinced that they’ll have a place in history, regales him with ancient wisdom (“All things in moderation”) and ancient heroes. Like a kid with a crush, Robert has a shrine to Alexander the Great posted up on his wall. Perhaps, Robert tells Joe, we, like Alexander, will be recognized as organizing conquerors, marching over a road of skulls to Shepherd’s Bush. Joe, of course, can barely remember to breathe through his nose.

Robert and Joe’s little idyll meets its serpent when Mary (Suzanne Sylvester) stalks in. Mary knows too much – about Robert’s past and about the basement’s future. Had Joe really been keeping up on his classics, he might have recognized Livia, the poisoner-queen. Suited and booted in Maalox pink, Mary paints the basement with her vitriolic harangues, turning man against man and outstripping their feeble efforts at ruthlessness.

Mr. Murphy builds characters like a master, but his plotting is still raw. Lisa Forrell’s direction plays into his nearly mathematical approach to the power in the room – whoever has it gets to sit in the big chair. During the long introductory scene, in which Joe learns at his master’s feet, “Tabloid Caligula” is still worthy of a banner headline. But Mr. Murphy falls into a common, expositional trap by the second half. The only engine for the piece, the thing changing the dynamic in the room, is Mary’s delivery of information. Though Ms. Sylvester snarls and sasses well, she can’t conceal the mechanics of these clunky revelations.

Not unlike Rachel Payne’s set design – a lively, but confusing mess – the piece and its production lose their storytelling thread. Had the characters not mentioned it in a late scene, I should never have known that the plastic-covered space was a tailor’s basement. Just as inexact, the immensely complicated backstory shared by Robert and Mary never seems very clear – it only materializes when some massive cruelty needs to be explained.

Of course, no one remembers tabloid stories for their syntax; they remember them for their characters. More colorful than a two-headed alien Elvis, Robert and his baffled sidekick are not easily forgotten. Even in a wobbling plot, the two of them remain memorable – so perhaps they’ll get their wish. They might have their places in history after all.

Until June 12 (9 E. 59th Street, between Madison and Park Avenues, 212-279-4200).