Queen Elizabeth III reigns in quiet solitude in "Perilous Night," which is receiving its world premiere at Nimbus Theatre. She conducts audiences with decorous grace and processes grandly, waving to her subjects. Never heard of Queen Elizabeth III? That might be because she's the denizen of an insane asylum, where, despite her best attempts at self-delusion, the real world still rudely intrudes on her regal presence with impertinent regularity.

Lee Blessing, the Minneapolis-born playwright best known for his Tony and Pulitzer-nominated "A Walk in the Woods," wrote "Perilous Night" in 2007, but Nimbus' production is this one-act's first full staging. Two of the characters — Elizabeth III and Harriet — are inmates in an asylum; the two other characters — Samuel and Carver — are their keepers. Over the course of one eventful night, the four of them wrestle, both figuratively and literally, with the meaning and consequences of power, gender politics and race. Not to mention, royal protocol and the proper way to address a sovereign.

This is hefty and often unwieldy material that can easily bog down in complicated argument, but director Liz Neerland and an accomplished ensemble manage to wrap their arms around "Perilous Night" with some success.

Shirley Venard, in particular, makes the most of the play's leavening humor in the role of Elizabeth, delivering wry zingers with regal authority and undertaking the most gruesome of measures against her captors with no-nonsense efficiency.

Her coolly detached performance is nicely counterpointed by Dana Lee Thompson's energetic, candid and unabashedly naïve Harriet, a younger inmate who envies Elizabeth's ability to transcend her surroundings. Harriet has stolen into Elizabeth's room to evade the vaguely ominous keeper who stalks the halls, but it's clear that she remains there, at least in part, as a way to assuage her own loneliness.

The first half of the play advances slowly, as the two women develop a carefully negotiated relationship. The tension ramps up dramatically, however, when the two orderlies appear on the scene.

Samuel, played by Ross Destiche, is the younger and less threatening of the two, alternately cajoling, whining and raging ineffectually to get his way. Kevin Carnahan's Carver, on the other hand, embodies seething wrath, ready into erupt in violence at the least provocation. At his appearance "Perilous Night" takes a stunningly abrupt turn from an intellectual exercise into a very physical confrontation.

"Perilous Night" is not without flaws. Nimbus' production, however, makes the most of the play's strengths, including nimble wit, layered characters and some plot twists as intriguing as they are unexpected.

Lisa Brock writes regularly about theater.