Then the gloves come off, although they were barely ever on in this litigious-minded comedy. As Veronica, whose kinship with victims has her writing about atrocities in Africa, Naomi Jacobson practically flinches at the insensitivities casually delivered by Alan, a corporate defender with an ear constantly to his cellphone. Alan, rendered flawlessly by Paul Morella, is working to keep a reckless big pharma company out of the soup. As directed by Joe Calarco, Jacobson and Morella often quarrel from opposite ends of the stage, as if they’ve been flung ridiculously far apart by opposed magnetic poles.

The gentler spouses don’t stay gentle for long. Michael, who runs a household wholesale business (doorknobs, plumbing parts), is played by the sizable, voluble Andy Brownstein, who is at his best when Michael breaks out some expensive rum and stops making nice. Annette, dressed in a power suit as sharp as her husband’s (she’s a wealth manager), is perhaps more empathetic than the rest. There’s a surprise in the first 30 minutes that accounts for that, yet Vanessa Lock still plays the part with a predatory prowl in her high-heeled step.

If you’re familiar with Reza and you hated her “Art” — the three-man fable about a friendship that sours when one of them buys an expensive plain-white painting — “God of Carnage” won’t convert you. The debate around Reza has to do with whether her accessible plays live up to her philosophical themes or if she’s just a boulevard entertainer in highbrow drag. The latter may be closer to the mark.

In “Carnage,” Reza’s trap does eventually seem artificial, and Calarco’s fast-paced production begins to huff a bit; at 75 minutes, it’s a runaway train. On the other hand, it’s refreshing to see a playwright revealing characters in real time, relying on a tricky current of words — pronouncements, feints, punch lines — to drive the show. Reza’s plays are pleasurable because they are events for actors.

At Signature, the cast is certainly taking its swings — Jacobson steaming and Morella purring, Brownstein angling and Lock insisting. (Plus everybody jumps and pouts.) The surprises have the pop of comic grenades as this foursome devours itself with flair.