In the Roundabout Theatre's new production of Stephen Sondheim's Assassins, presidential killers — and wannabes — all converge on a unique locale that is part shooting gallery, part sideshow, and part gallows. Designed by Robert Brill, who received a Tony nomination, the setting is both menacing and oddly cheerful.

With its wooden beams extending upward beyond the proscenium, the set resembles the pylons of a classic wooden roller coaster (think Woody Allen's childhood home in Annie Hall). That was exactly what Brill had in mind when he originally conceived of the set back in 2001, when the show was first planned but later scrapped after 9/11. “This design process was, quite literally, a roller coaster ride,” he says. “The final design was influenced by our original ideas as well as with what we are influenced by now. When 9/11 occurred, I was on a plane to Buffalo and then continuing on to Toronto where 75% of the original set was complete.”

One of Brill's inspirations was a haunting photo of a roller coaster on top of a Holiday Inn in Las Vegas that was illuminated at night. “Only in Vegas could you find a roller coaster lit that way,” he says. “They are really provocative structures and are extremely dramatic and theatrical. They are begging to have events staged around them.”

The set, populated by John Wilkes Booth, Lee Harvey Oswald, Squeaky Fromme, John Hinckley, and company, evokes the underbelly of an abandoned amusement park or a traveling carnival that was left to rot and fester. “I wanted to look underneath the bleachers,” Brill says. “You can almost tell a story entirely from what has been left behind. The things that fall through the cracks let you know what has happened that day, but instead of a holding tank for the shows action, director Joe Mantello suggested that this is where the characters live; they never come up top because they are on the margins of society.”

Brill never once considered designing the set as the actual scenes of the crimes or attempted crimes. While it might have been tempting to recreate Ford's Theatre, Dealey Plaza in Dallas, or the World Expo in Buffalo, Brill and Mantello wanted an environment that could easily evoke those places but could also act as a staging area for this motley cast of characters. However, one real crime scene is brought to life: the Texas Schoolbook Depository. The scene occurs close to the end of the show when the assassins — led by Booth — attempt to persuade Oswald to take a shot at JFK instead of taking his own life.

The transformation is seamless; the introduction of a few cardboard boxes, warehouse light fixtures, and a row of windows along the back wall takes the audience to Dallas on November 22, 1963. “We didn't want the stage to completely transform but rather that we suddenly realize we've been here all along,” Brill explains. “It's very provocative and very simple because everyone knows where they are and what's about to happen.”

Aside from being on the outer margins of American society, the assassins all had their own obsessions and underlying reasons for what they did-Hinckley's Jodie Foster addiction, Fromme's Charles Manson dependency, Booth's pro-Southern fanaticism, Samuel Byk's junk food and beer (he wanted to crash a 747 into Nixon's White House), and so on — and that was another aspect that Mantello wanted to include in the production. The most obvious way seemed to be through props. “One of our impulses was to put them in a clear booth, and, as the show progresses, the booths get more and more cluttered with pictures of Lincoln or Jodie Foster or junk food or whatever,” Brill explains. “By the end, they would walk out of their booths for the finale.”

That idea changed once the set became more fully realized. In the current incarnation, the assassins take their places among the beams and scaffolding in stalls furnished with targets shaped like the silhouettes of the presidents they wished to see dead. The targets are present throughout most of the show but have further significance as each one of the characters takes their place alongside an image of their victims (or intended victims).

Another idea that changed linked directly to the side show/shooting gallery concept. The Proprietor (the narrator and supposed operator of the shooting gallery) tries to get the characters to line up and take shots. Like a traditional carnival, prizes are needed to entice rubes to throw down their money, and these prizes had originally taken center stage, but that was scrapped soon after rehearsals moved into the theatre. “Once we got into tech, we realized that the composition wasn't working and the focus wasn't where it needed to be,” Brill says. “So we tried to find a space for them on a set that was already congested with more structure than I've dealt with in a long time.”

The result involved hanging the prizes on either side of the stage from chains that were lowered at the beginning of the show. Among the prizes offered were money and a mannequin dressed like Jodie Foster's character in Taxi Driver. Originally, as each assassin takes focus, the prizes would disappear as they retire to their given stalls, but according to Brill, “too many prizes glommed up the visual, so we ditched them.” Now, the prizes all fly out after the opening number.

The prizes and booths were brilliant ideas, but both Brill and Mantello felt that they stole the focus from the set itself which is an imposing structure comprised of real, solid beams, planks, and posts that are all fire-treated. However, when it all arrived by train car at the studios of Great Lakes Scenic in Toronto, Brill was aghast at the sheer size. “You can't imagine how much lumber that really is!” he says. Aside from Great Lakes, Atlas and The Shop also built some scenic elements, and Scenic Technologies created the automation for the show.

For a designer who was a magician as a kid, an apprentice at an architectural firm, and admittedly obsessed with space and structure, Brill is delighted by the scene onstage at Studio 54 night after night. “I'm really thrilled with the end product,” he says. “When you have a structure like this that is bearing a lot of weight, it is really a feat of engineering.”