“It seemed to be one of life’s wonders,” observes Sherwyn Sexton, the not wholly unlikable cad at the center of Fay Weldon’s lively if sometimes frustrating new novel, “Before the War,” “that nothing happens and nothing happens and all of a sudden everything happens.”

“Let’s Not Do That Again” is a political comedy of manners that reads like the love child of Page Six and a long episode of “Veep.”