Celebrated novelist and poet Margaret Atwood narrates excerpts from her next novel, “Year of the Flood,” to be published in September. For this special event, several local actors and a small chorus will join the Booker Prize-winning author to dramatically stage select scenes. Atwood has written more than 35 volumes of poetry, fiction and nonfiction, including the best-selling novels “The Handmaid’s Tale” and “The Blind Assassin.” She uncannily anticipates issues that will preoccupy the public and expresses the potential ramifications in impeccable prose.