Echoes in Death — J.D. Robb

As NY Lt. Eve Dallas and her billionaire husband Roarke are driving home, a young woman―dazed, naked, and bloody―suddenly stumbles out in front of their car. Roarke slams on the brakes and Eve springs into action.

Daphne Strazza is rushed to the ER, but it's too late for her husband Dr. Anthony Strazza. A brilliant orthopedic surgeon, he now lies dead amid the wreckage of his obsessively organized town house, his three safes opened and emptied. Daphne would be a valuable witness, but in her terror and shock the only description of the perp she can offer is repeatedly calling him “the devil”...

While it emerges that Dr. Strazza was cold, controlling, and widely disliked, this is one case where the evidence doesn't point to the spouse. So Eve and her team must get started on the legwork, interviewing everyone from dinner-party guests to professional colleagues to caterers, in a desperate race to answer some crucial questions:

What does the devil look like? And where will he show up next?