N Is for Noose — Sue Grafton

Tom Newquist had been a detective in the Nota Lake sheriffs office--a tough, honest cop respected by everyone. When he died suddenly, the town folk were sad but not surprised. Just shy of sixty-five. Newquist worked too hard, drank too much, and exercised too little.

Newquist's widow, Selma, didn't doubt the coroner's report. But still, she couldn't help wondering what had so bothered Tom in the last six weeks of his life. What was it that had made him prowl restlessly at night and brood constantly? Determined to help Selma find the answer, Kinsey Millhone sets up shop in Nota Lake, where she finds that looking for a needle in a haystack can draw blood--very likely, her own....