Playwright Tony Kushner won two Obies, two Tonys, the Pulitzer, and, last month, an Emmy for his brilliant play "Angels in America." In his new play-in-progress, "Only We Who Guard the Mystery Shall Be Unhappy," Kushner explores the mystery of the mistress of beige, First Lady Laura Bush. In the first scene of the new work, Mrs. Bush goes to heaven to read the Grand Inquisitor segment of "The Brothers Karamazov" to dead Iraqi children; in scene two, she argues with Kushner himself about the place of politics in art. The play gets an election-weekend reading this Friday evening at Next Theatre. See details in Slowdown.