Kittyhawk Down ( Challis and Destry mysteries 2) - Garry Disher

The once-peaceful beach resort of Bushrangers Bay, not far from Melbourne, is the site of multiple crimes that must be investigated by Homicide Squad Inspector Hal Challis and Sergeant Ellen Destry of the Mornington Peninsula Police Force. A toddler is missing; an unidentified corpse has been fished from the sea; cars are being stolen and torched; letter boxes are being burned. And then one of Challis' own friends, Kitty Casement, who runs an aerial photography service and flies a Kittyhawk, is murdered.

Figuring out the connections and identifying the criminals absorbs all the energy and intelligence of this cast of sympathetic but complicated policemen and women.