Book 1 of Adam Dalgliesh
 
Dalgliesh.

I've heard of him - ruthless, unorthodox, and working always against time. When the body of Sally Jupp is discovered in her bedroom - the door bolted from the inside - the occupants of Martingale House are sure that the blame for this unthinkable crime will fall on an unknown intruder. But each of the household is hiding a secret that could shed light on the murder.

And there's only one man who can sift through the layers of deceit and pretence to unmask the truth: Detective Chief Inspector Adam Dalgleish.
 
P.D James