P. J. Tracy

On a bitterly cold winter night, Kelly Ramage leaves her suburban home, telling her husband she's going to meet a friend. She never comes back. When her body is discovered, murdered in what seems to be a sex game gone horribly wrong, Detectives Gino and Magozzi take the case, expecting to find a flirtatious trail leading straight to the killer. However, Kelly's sinister lover has done a disturbingly good job of hiding his identity. This isn't his first victim. And she won't be the last...

Book 10 in the Monkeewrench series.

Elderly Morey Gilbert is found lying dead in the grass by his wife, Lily, with a bullet hole in his skull. It looks like an execution, and soon the whole city is fearful as new victims are found, killed with the same cold precision. All elderly. All apparently blameless. Detectives Gino and Magozzi race to uncover a connection, and the answers, it seems, are buried in a terrible past...