At ART, a Nero who plays guitar

CAMBRIDGE -- Music floats through the rehearsal room -- everything from twangy guitar chords and bass to snippets of Schoenberg's dissonant piano chords and a mezzo soprano singing an aria. Actors in the American Repertory Theatre production of "Britannicus," which starts previews tomorrow, are singing, playing, and fussing with props in two areas on opposite ends of the space. One woman paces silently back and forth while two actors sit near her, watching the proceedings.

The rehearsal appears chaotic, yet no matter where you look, each scene has an intensity that is a little unnerving.

"I like messy things," says director Robert Woodruff with a sly smile. "The trick is to keep the audience focused in one place for the essential dramatic moment, and then allow them to drift to action happening elsewhere. If you have enough structure, it works."

Woodruff's skill at juggling multiple scenes for dramatic effect has become his trademark at the ART, with the contrasting imagery of father and son in "Highway Ulysses," the visual burden of past deeds in "Oedipus," and the counterpoint of earth and the underworld in "Orpheus X."

With "Britannicus," Woodruff returns to a classic, this time bringing contemporary attitude to Jean Racine's 18th-century thriller about the infamous Roman emperor Nero. The play follows Nero's rise to power through the humiliation and destruction of his stepbrother Brittanicus, whose beloved, Junia (Merritt Janson), is the focus of a jealous love triangle.

"The action of 'Brittanicus' happens out in this open area," Woodruff explains, "but all of that comes out of scenes that play out behind closed doors."

So the set design, by Riccardo Hernandez, allows room for bedrooms on either side of the space -- one for the 20-year-old Nero (cluttered with a motorcycle helmet, beer bottle, and other young-man debris), the other for his mother, the manipulative Agrippina (played by the OBIE-winning Joan MacIntosh, last seen at the ART in 1986's "The Balcony"), whose space holds prescription bottles and a closet full of clothes.

Written during Louis XIV's rule in France, "Britannicus" was seen as a cautionary tale, encouraging the Sun King not to take the path of cruelty that became Nero's legacy. In the drama, Nero (played by Alfredo Narciso) is just coming into his own as emperor and is flexing his muscle as the most powerful man in the world. After relying heavily on his mother and other advis ers, he wants independence, but the arc he follows goes from weak and timid to vicious and cruel. An honest, upright man, Britannicus sees his claim to the throne, then his true love stolen from him by Nero.

"Nero wants his freedom," Woodruff says, "and he thinks he can find it in this woman, Junia. Unfortunately Junia loves Britannicus, and Nero can never be that other boy."

Kevin O'Donnell, the Cohasset native and Emerson College grad who plays Nero's rival, says that "in some ways Britannicus and Nero are like two halves of the same person. Britannicus is good and wears his heart on his sleeve, while Nero chooses to be mean and nasty. In fact, both Alfredo and I auditioned for Nero."

O'Donnell, who has an open, eager face, says his role has its challenges. "It's tough," he says. "In one scene after another, you get crushed. After losing everything else, he believes even his girlfriend has betrayed him. It's all about submitting to this tyrant's will, but the stakes are so high."

Narciso says that playing the bad guy has been fun, but it also takes a toll.

"At one point Nero says, 'I'm tired of being loved, I want to be feared.' When you start to think that way, it brings up some dark things," says Narciso, who's also composed some original music for the production. "I have to find the moments where he's human, where he might have made a different choice. It's hard to know how much is calculated. But I've been having nightmares because these scenes are so intense."

Woodruff uses a variety of tools to ramp up that intensity, including the music, chosen to emphasize Agrippina's sense of loss and Nero's lack of boundaries, and video projections that will emphasize the intimate emotional machinations taking place. "It's all about eyes and tears," Woodruff says.

O'Donnell says Woodruff's layering suits the play's tone and pace well. "The action builds to this incredible climax," he says. "Racine's writing is kind of schizophrenic, with everybody thinking in four different directions."

Narcisco agrees. "All of the intrigue builds to something shocking," he says. "The layered way Racine writes it brings you close to these characters while keeping you off balance about where it's heading."

And while the story is steeped in the politics of ancient Rome and filtered through 17th-century French sensibilities, a simple truth about individuals and politics resonates just as well today, says Woodruff.

"I think the story looks political," Woodruff says, "but political motivations are always personal. People hide behind dogma, but their sense of justice or rightness comes from a very personal place."