It's late, it's dark, and someone is killing the lesbians of Citytown. Two nurses slink through the hallways and waiting rooms of Citytown General Hospital, knowing that all around them is a death house. Nurse Silver is a stout, bearded woman who would seem better suited in a butcher shop than a hospital. Nurse Cherry is glaringly adorable, and describes herself best as "virginal, deceptive, and non-virginal." Horror is in the air, and thunder sounds in the distance, like a giant, perverted brain synapse. So begins our Mister Murdery.

The Cardboard Box Theatre's Mister Murdery is ingenious, lovely, and has a psychotic violent streak. In a stylish affront to the conventional murder mystery, Stephen Karam has done for playwrights what Richard Speck did for mass murderers. Citytown is a world unto itself, ripped from the diary of the Marquis de Seuss, where super-rational wordplay is at work, and people perform as fetishized, undercover versions of themselves.

As Nurse Silver, Darius Pierce is a calculating dynamo, moving like a transvestite wrecking ball. Nurse Cherry (Kerry Silva) is the coquette, the heartbreaking darling that always seems last on the killer's hit list. Against a viscera-pink background the players share a dance that is half grace and half brutality. Terror is a delicate, pretty thing, made of white nurse's uniforms and bubble gum.

For a play about sexually tense nurses and lesbian slayers, Mister Murdery is most amazing in its subtlety. The script weaves post-P.C. plays-on-words with the jargon of bureaucracy. The Greek chorus takes the form of an omniscient radio, transmitting skewed news and corporate-sponsored ghost stories. If one gets lost in the bipolar shuffle of tongue-twisters and mind-fucks, it's only because the play is working very, very well.

Be warned: Mister Murdery wants to wrench your gut and split your sides. At the end of the show, the front row of the audience is left with their minds blown out the sides of their heads; the rest of the house is sent home with beautiful nightmares. TOUSSAINT PERRAULT