Song parodist Spike Milligan once blamed his limited--though devoted--appeal on the fact that his comedy songs were too lowbrow for the highbrows and too highbrow for the lowbrows. The same paradox has dogged playwright Christopher Durang, whose wild, bitter, piercing sense of humor made a long-running hit of the one-act Sister Mary Ignatius Explains It All for You, but whose similarly biting full-length works have been strangely underappreciated. In essays that introduce The Marriage of Bette and Boo, Beyond Therapy, The Idiots Karamazov, A History of the American Film, and three other brilliant, challenging works, Durang shares his anxieties about his life and writing, and his recurring nightmare of being panned again and again by Frank Rich of the New York Times. Durang's plays may be better read than seen, but you've got to love a guy who imagines a movie titled Seven Brides for Twelve Angry Men.