After a well-received Off-Broadway run in 1991, the show's transfer to Broadway was canceled because the outbreak of the first Gulf War made its subject matter seem unsuited to the charged political climate. A decade later, Assassins was resurrected, only to be abruptly withdrawn again because of the 9/11 terrorist attacks.

Sondheim's controversial creation has finally arrived on Broadway, in a production by the Roundabout Theatre Company, but what's on the stage of the Studio 54 Theatre adds the issue of timeliness to the sensitive questions of taste that have inevitably dogged Assassins.

The production features a cavalcade of kooks, loonies, losers and loners in a sardonic tour of the warped psyches of presidential assassins and would-be assassins, from John Wilkes Booth to John Hinckley. But it comes along in an era forever changed by the catastrophe that forced that second cancellation.

We worry today not so much about a single shattering shot fired in the name of individual grievance as about the fanaticism and hatred that lead to mass slaughter of the innocent and uninvolved in Bali nightclubs and Madrid trains.

Director Joe Mantello stresses the carnival as the governing metaphor of Assassins. It serves as a telling emblem of the underside of the American dream. The gist of the show, which offers a rich score and mordant lyrics from Sondheim and a problematic book by John Weidman is that - in one way or another - the assassins feel betrayed because they have not reaped that dream's promise.

Assassins couches that disappointment in vivid and garish shooting-gallery images of our violent gun-nut culture. Weidman's book says we should not be surprised by the way these thwarted souls vent their frustrations. His argument will strike most people as painfully obvious and old hat, but it is here advanced as if it were an arresting revelation.

Assassins was inspired by an earlier musical written by Charles Gilbert Jr., who was then musical director of Theater Express in Pittsburgh and is currently associate professor and head of the musical theater program at Philadelphia's University of the Arts.

Sondheim's musical contrasts an often playful treatment of the delusions of this murderers' row with the terrible deeds that resulted. The killers are united by the song that begins and ends the show, "Everybody's Got the Right." At the conclusion, this delightfully subversive inspirational piece has the cast members pointing their guns at the audience.

Weidman and Sondheim, whose striking score draws together many currents of American music, have conjured a sort of killer's limbo and a parade of hit men and women - one that takes us on an unchronological journey from the barn in Virginia where the crippled Booth died after shooting Abraham Lincoln to the Texas Book Depository, where, in the show's most dubious development, the assassins of the past egg on Lee Harvey Oswald.

Because nine successful and would-be assassins have to be covered, there is no space for anything more than a cursory look at their motives. And sometimes reality intrudes jarringly.

Those old enough to remember where they were when President Kennedy was shot (Sondheim captures the shared national grief in the very moving "Something Just Broke") will find the Oswald episode very near the bone.

The mad scheme of Samuel Byck, the tire salesman who tried to hijack a commercial jetliner in 1974 and planned to crash it into the White House, now has a chilling resonance; the laughter in the theater has a distinctly nervous edge. And it is hard to watch the light traversal of John Hinckley's story without thinking of Ronald Reagan, now lost in the mists of Alzheimer's disease.

Not surprisingly, the more flamboyant roles in Assassins come off best. Michael Cerveris is a suavely manipulative Booth, and Mary Catherine Garrison and Becky Ann Baker have fun with the scatterbrained derangements of Lynette "Squeaky" Fromme and Sarah Jane Moore.

Both Moore and Fromme missed when they took their shots at Gerald Ford. It's gratifying to have a musical for grown-ups making it belatedly to Broadway, but, in our drastically altered world, Assassins itself isn't always on target.