By the time the 21st century rolled around, Ruth Rendell, who turned seventy as its dawn, had published forty-six novels and six short story collections over thirty-six years. That is a lot of writing, but the seemingly indefatigable author kept on going, producing another score of crime novels and another short story collection in the fourteen years left to her. There were nine non-series Rendells (the last published posthumously in 2015), six Wexfords and five Barbara Vines. There was...