The Boyfriend by Thomas Perry

Catherine Hamilton is a beautiful, strawberry blond escort. When she trusts the wrong man, she winds up dead. Her parents hire ex-cop Jack Till to find out what really happened to their daughter when the cops don't seem to be making any progress. He soon discovers that Catherine is only the latest in a string of beautiful, strawberry blond escorts who have turned up dead. And he begins to suspect that it isn't a coincidence.

The Boyfriend involves plenty of suspense and knuckle-biting action. It's a great summertime read.