In David Lindsay-Abaire's Wonder of the World, people are crushed by innocuous things—pillows, peanut butter—and small decisions backfire in large ways. Lindsay-Abaire, who won a Pulitzer for drama this year, traffics in brutal sympathy: Our human irregularities are forgivable, but they're still totally fucking weird.
Cass Harris (Gigi Jhong) is packing to leave her husband, Kip, because she discovered his secret—something harmless but gross. The grossness of the secret (which I will leave you to discover on your own) is only part of the problem; Cass is more shaken by the distance it implies: "I had no secrets. Nothing extra inside me." As penance, all Kip can offer is a cold, quivering aspic ("TRY THE FUCKING ASPIC!"). It's not enough.
Armed with a list of life goals ("ask big questions"; "make friends with a clown") and a suicidal, barrel-toting, alcoholic sidekick (Lois, played by Ellen Dessler), Cass heads for Niagara Falls. She is manic and scattered, but kind of happy. She meets a lot of other people, whose lives are also broken. The play ends in group therapy, which ends in The Newlywed Game.
Lindsay-Abaire's script is snide and funny and sweetly meta in all the right places ("Hey, you want to strike up a conversation?"); the production is competent, if rough around the edges. ReAct Theatre (which also produced Lindsay-Abaire's Kimberly Akimbo in 2005) leans rather heavily on the comedy—Wonder's dramatic moments are frail. But it doesn't really matter. Life is problematic; problems are for laughing at; laughing makes for good theater. Wonder of the World is good. 
