Careless in Red by Elizabeth George

From #1 New York Times bestselling author Elizabeth George, a stunning mystery featuring Detective Inspector Thomas Lynley that explores the perfect crime.

After the senseless murder of his pregnant wife, Detective Superintendent Thomas Lynley hands in his badge and walks out of Scotland Yard. He goes home to Cornwall. The only way he can deal with his painful memories is to hike the trails over the cliffs of the Cornish coast. There, on the forty-third day of his walk, he finds the lifeless body of a young man, dead from a fall.

Thus begins a quest to unmask a clever and ruthless murderer. But this time, Lynley’s not in charge. He’s a witness—and possibly even a suspect. The vastly understaffed local copper in charge of the investigation soon figures out that Lynley can help. So can his former associate Barbara Havers, whom Scotland Yard sends to Cornwall, ostensibly to assist in the investigation, but unofficially to keep an eye on Lynley and maybe lure him back to his job.