Tête-à-Threat: McEvoys Cagney impersonator disturbs the peace. s Cagney impersonator disturbs the peace.

Consider the queasy cocktail of pity and bemusement with which you regard a cover band. A professional impersonator has to be worse, right? Not a mimic—an impersonator, whose art, or skill—or mania—is to adopt the appearance, speech, demeanor, and movement not of other people, but of one other person.

There’s something creepy there already, but when the object of the forgery is the supremely creepy Jimmy Cagney, best remembered for mashing a grapefruit in Jean Harlow’s face in the 1931 gangster flick The Public Enemy, well, don’t be surprised to find your skin trying to slither under your chair.

That element of the grotesque, Barry McEvoy’s mercurial performance as Tommy Black, a semiprofessional Cagney doppelganger marooned in embattled and impoverished 1980s Belfast, gives Scena Theatre’s “The”-free Public Enemy a hypnotic lure, one that abides even after things erode in the second half from predictable to confusing to comical.

Kenneth Branagh, who was born in Belfast, wrote and staged this bizarre character study/crime caper/political parable a couple of years before Henry V made him a movie star among English professors. The show isn’t openly self-referential, but it echoes elements of the original film, and its MacGuffin is, in fact, a videocassette of that movie. Confused? Suffice it, then, to observe that director Robert McNamara is better at conjuring the claustrophobia and desperation of Thatcher-era Belfast than he is at untangling the morass of motivations that make Tommy try to manipulate life into imitative art. At least it’s clear enough why Tommy, a sensitive guy among bullies, would seize on Cagney as figure to emulate: He was a titan who could sing and tap-dance his way through “Yankee Doodle Dandy” without diminishing his rep as one of the screen’s all-time baddest outlaws one iota.

Tommy has avoided being drafted into the conflict by convincing his fellows that he’s a little nuts, staying in and perfecting his Cagney act while his contemporaries get drunk and shoot each other. The background elements of Branagh’s scenario are archetypal where they aren’t lifted from the film—Tommy’s got a dead dad and a drunk mom who favors her dreamer son over his buttoned-down brother who’s still trying to land a job and take care of business. We even get a trenchcoated, seen-it-all detective for a narrator, whom Branagh will task with delivering the story’s none-too-subtle moral that thugs are thugs, ideology or no. “Join a mob and call it a cause,” he says.

Though we’re never absent a pretty accurate idea of where all this needs must go, it takes its time getting there, and in the first act, the meandering is pleasant. There’s a sensuous delight to those accents, and to Michael Stepowany’s grimy set, and to the way Matt Dougherty, in the role of the expository dick, talks like Stephen Rea and looks like McGruff the Crime Dog. When Tommy tells Kitty, his new girlfriend, to remember to pick up grapefruit while she’s at the store, you yearn for more moments like that.

Once Tommy sets out on a fateful errand to a video store in a Republican-controlled neighborhood, the telling turns hazy. (Perhaps it was the fog machine, ever on duty in the H Street Playhouse.) Unable to stop quoting Cagney lines even long enough to reassure his panicked best friend and girlfriend (Daniel Kenner and Annie Grier, respectively), Tommy may simply have snapped, or may be trying to pit the warring factions against one another, Yojimbo-style—er, Cagney–in–The Public Enemy–style. (But weren’t the Republicans and Unionists openly at war already?) Still, the tragedy of Tommy’s ineptitude and its consequences for those near to him resonates. Or it would, if the production didn’t subject him to a leaky end. This is second show I’ve seen at the H Street playhouse that climaxes in rainfall, and the impression remains the same: Rain looks great on film. On stage, you just feel kind of embarrassed for the actor standing under the shower, and you wonder what kind of drainage system they have.