NEW YORK - Nice guys finish last. Fat girls finish laster. Nice fat guys finish lastest. So we learn from the Neil LaBute trilogy, starting with

The Shape of Things

, continuing with

Fat Pig

, and concluding with this MCC Theatre world premiere of

reasons to be pretty

. Amusing, insightful, and slimy - the LaBute usual - this newest installment charting the desperate and vile misunderstandings between the sexes is also disappointing, despite some terrific acting.

The setup: Two couples work in a warehouse. Before Act 1 begins, Greg (Thomas Sadoski) apparently has said something disparaging about his girlfriend's face. Steph (Alison Pill) confronts him in a wild, violent fight, beginning the play at top decibel. He threatens to call the cops. She threatens to murder his fish. Later she will publicly read a catalogue of his physical flaws - hair to toes - aloud in the food court at the mall. Greg, who reads 19th-century classics (Poe, Hawthorne, etc.) meekly, lovingly absorbs her abuse just as he tolerates his pal Kent's (Pablo Schreiber) bullying.

Every relationship in the play will hinge on appearance: Kent's wife, Carly (Piper Perabo), tells us about the burden of being pretty - guys follow her around supermarkets, often with their kid in the cart - while her husband philanders with a new woman whose blue/green eyes drive him crazy. Kent - self-consciously hunky and sexy - mocks Greg's taste in women. Eventually the two guys fight like boys in a schoolyard; it's more a temper tantrum than a brawl.

Betrayals (at the level of tattling, although with enormous adult consequences) pile up, as it becomes clear that these four people are the blue-collar versions of the characters who populate LaBute's earlier plays and movies (The Company of Men, Nurse Betty). In The Shape of Things, a graduate student uses her unwitting lover as her thesis project, reshaping him as human sculpture. In Fat Pig, a dot-commer and a fat woman fall in love, but he caves under his coworkers' mockery and dumps her. In The Mercy Seat, a married man who has spent the morning of 9/11 at his lover's apartment instead of his World Trade Center office stares at his endlessly ringing cell phone as his wife keeps calling. As Kent says, "That's what most guys do - ride that wave to shore."

But unlike those scripts, reasons to be pretty ends with a puerile monologue: Greg explains that "beauty is of no consequence but we chase it anyway," providing cliche magazine and movie examples. He tells us he learned in an art-history course that "beauty is subjective"; his big discovery is "life is short." And his advice: "Be nice."

In the program's "Note from the Playwright," LaBute wishes he were "a braver person." He has reliably been a brave and shocking playwright, but reasons to be pretty seems to lack theatrical courage.

reasons to be pretty

Through July 13 at Lucille Lortel Theatre, 121 Christopher St., New York. Tickets $59. Information: 212-279-4200 www.ticketcentral.com.

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