Twelve Angry Men starts portentously, with a voice-over admonition from an offstage judge, and never really strays far from that suffocatingly superior territory.

But then, Reginald Rose’s determinedly civic-minded 1954 drama was written for TV, wasn’t it? And if the combined talents of Henry Fonda and a prodigious supporting cast turned Sidney Lumet’s 1957 film version into the stuff of screen legend, the Keegan Theatre’s just-passable local production is nothing if not evocative of the simple moralizing we associate with the boob tube. There are a few decent performances here, it must be said, and perhaps even a finely crafted portrayal or two, but under the bland weight of director Ellen Dempsey’s good intentions, the story—about a righteous man who talks his peers on a blithely biased jury out of an unjust murder conviction—plays like nothing so much as a 90-minute public service announcement.

Oh, the script can be clever enough about the way it reconstructs the events—a knifing, two seemingly solid witnesses, a weak defense in the face of an aggressive prosecutor—that bring the characters to this jury-room sweatbox on this oppressive summer afternoon. Without ever seeming to stop for an obvious flashback, Rose offers up a bit more information about the crime each time Juror No. 8 (disagreeably smug Daniel Ladmirault) challenges his colleagues’ assumptions about what they’ve seen on the witness stand.

Likewise canny, from a purely dramaturgical viewpoint, is the way Rose structures the arguments with which No. 8 sways the more analytical of his fellow jurors: A stopwatch-timed reconstruction of one witness’s likely movements, a point of logic about an el train and its deafening noise, a revelation about the other witness’s eyeglasses—each adds a frisson of police-procedural suspense to the otherwise talky proceedings.

Every so often, though, the script betrays itself as written for another medium. Most markedly awkward are the sidebar conversations during the jurors’ first break from deliberations; on screen, they might be convincing as whispered exchanges shot in close-up, but the realities of live theater will leave audiences wondering why the increasingly contentious dozen have paired off for private conversations, only to conduct them in tones that everyone in the claustrophobic room could overhear.

And it’s not as if they haven’t been talking enough about themselves. As the conversation in Mark A. Rhea’s deliberately drab, appropriately cramped jury-room set veers from the bare facts of the case to the banal facts of the jurors’ lives, Rose means to reveal something about each man’s prejudices through his various offhand remarks. The smarmy self-assurance of the smoke-blowing advertising rep, the tough-guy bluster of a man who “wanted to vomit” when his kid ran away from a schoolyard fight, the smoothly avuncular utterances of the well-dressed, well-spoken businessman—every conversational sally says something about why these men were inclined to vote “guilty” on the first round.

But even if this sort of thing passed for subtle character definition in the ’50s—and it probably didn’t, seeing as how we’re dealing with the kind of screenplay shorthand required to sketch 12 personalities and a plot in an hour and a half—it’s definitely got an air of obviousness about it now. Contemporary audiences will have most of these guys pegged before they open their mouths—which makes all the chattering superfluous at best. And, sure enough, the evening sags nearly every time Rose departs from the testimony in the case to dwell on the personalities charged with interpreting it.

The few exceptions come courtesy of several crucial supporting players: Eric Peterson as Juror No. 6, “just a workin’ man” but an essentially decent one; Stephon Walker, in a quiet, sensitive performance as Juror No. 11, an immigrant who, in Rose’s hands, is a degree too much a symbol of the freedoms the others take for granted; Richard Jamborsky, painfully self-aware and sad as Juror No. 9, an old man who understands how someone like himself might come to distort what he saw at a sensational crime scene, if only to keep the spotlight turned his way that one moment longer.

It’s these performances, along with the relatively measured work from most of the remaining ensemble, that give the production the beginnings of emotional heft despite the actorish mannerisms of Tim Getman (Juror No. 12, the too-jocular ad salesman) and the one-note bellicosity of David Jourdan as Juror No. 3, the last holdout.

Jourdan’s character, written to embody not vicious racial hatred (that’s No. 10) but the most pervasive kind of simple, obtuse prejudice, is the punching bag for Rose’s liberal hero, the cardboard target for the author’s well-aimed arguments about logic and principle and fairness. But Juror No. 3 is crucial enough to the story that Rose leaves wiggle room for the audience to sympathize with the character, revealing just enough about his middle-class, Middle-American conditioning to make his hard-heartedness understandable, if not acceptable.

It probably says something about Jourdan’s performance that this troubled man’s climactic breakdown—the linchpin of the play’s last moments—comes across as hollow, stagey, and utterly unaffecting. And it says something about the production itself, and about how badly the script is holding up in the new century, that you won’t care much; when Twelve Angry Men turns out to be about a few hotheads and a handful of mildly disturbed guys, it’s hard to get especially peeved over one actor’s failings. CP