Private investigator Roland Ford has settled into a routine life.  Still gutted by the death of his wife in a plane crash, he rents out the villas on his ranch in California to friends and relatives and just lives life, taking easy cases when he gets bored.  Then a friend from the past, Lindsay Rakes comes to him with a problem.  She has been receiving threatening letters and is getting scared.  She doesn't want to go to the police because she is in the midst of a custody fight with her ex-husband over her young son.

Ford moves Lindsay into one of the villas and starts to investigate.  Some years before, Lindsay was in the military and her job was as a drone operator.  Along with two others, they targeted and dropped bombs on terrorist targets in the Middle East.  Lindsay has checked with her teammates and both of them have also received the same threatening letters.  She asks Ford for help and he reluctantly agrees.

But Ford knows his limits.  He knows he needs more help and contacts Joan Taucher, an FBI agent he knows who is focused on stopping the next terrorist attack before it happens.  She has never forgotten that some of the 9/11 terrorists learned to fly in Santa Barbara.  Together they start to investigate and learn that the drone team had made a mistake that cost the lives of nine doctors and nurses.  Could this be a relative of one of those innocent victims?  Then one of the drone team is found beheaded which ups the stakes considerably.  Can they find the killer before he finds Lindsay?

This is the second novel in the Roland Ford series.  Parker has created an investigator who is a sympathetic character.  There are interesting side characters in the friends and relatives who live on Ford's spread and the investigation is fast and furious.  This book is recommended for thriller readers.