At first glance, Sarah Ruhl's comedic drama possesses an alarming potential for cliché. There's the hard-charging, career-consumed doctor, Lane (Hollis Resnik); her doormat housewife sister, Virginia (Karen Landry); and, mediating the two, Brazilian, joke-loving maid Matilde (Lisa Rafaela Clair). So it's a pleasant surprise to see this Mixed Blood production wed a breezy, bittersweet tone to Ruhl's inventive twists and turns, in which each female character is changed by several degrees and avoids the taint of the commonplace. The early going concerns machinations in which the depressed Matilde (Clair brings wide-eyed, oddball charm to the role) is rescued by Virginia, who turns out to be so desperate for meaningful activity that she's willing to do Matilde's work for her (Landry works within the confines of a recessive role, latching hard onto Virginia's bizarre morbid streak). Director Stan Wojewodski Jr. keeps the pace lively. By the time we meet Lane's doctor husband, Charles (Stephen Yoakam), we've learned that he's left his wife for an older cancer patient named Ana (Olivia Lawrence). Yoakam and Lawrence also appear in fantasy sequences as Matilde's parents, idealized romantics constantly in thrall to one another, while in the main action Charles and Ana appear similarly blissed out, to Lane's considerable consternation (Resnik gets one of the best lines of the night when her character's soon-to-be ex-husband suggests that his wife and his lover join him in some sort of lovefest. Her response: "This is not a foreign film!"). Eventually, Ana's health takes a turn for the worse, and Lane tries to convince her to seek medical treatment. Resnik and Lawrence do some of the best work here, as characters feeling their way palpably into the forest of their individual futures. There are moments in the second act when the sentiment threatens to turn cloying, but the quality of the performances tends to right things and accent the idiosyncrasies of the script. By the end, a running motif about Matilde's search for the perfect joke (she delivers the show's only actual joke, in Portuguese, to open the evening) leads to a killer line that frames the action almost perfectly. The Clean House, with its oddball charms, manages to sneak up and deliver an unexpected sense of profundity.