Title:  Forty Thieves

Author:  Thomas Perry

Sid and Ronnie Abel are a first-rate husband-and-wife detective team, both ex-LAPD.  Ed and Nicole Hoyt are married assassins-for-hire living in the San Fernando Valley.  Except for deadly aim with a handgun, the two couples have little in common–until both are hired to do damage control on the same murder case.  The previous spring, after two days of torrential rain, a body was recovered from one of the city’s overwhelmed storm sewers.  The corpse was identified as James Ballantine, a middle-aged African American who worked as a research scientist for a large corporation and was well liked by his colleagues.  But two bullets to the back of the head looked like nothing if not foul play.  Now, with the case turning cold, Ballantine’s former employers bring in the Abels to succeed where the police have failed, while the Hoyts’ mysterious contractors want to make sure that the facts about Ballantine’s death stay hidden, no matter the cost.

As the Abels and Hoyts proceed on their respective missions, both couples find themselves up against an enemy the likes of which they’ve never seen.  Dramatic car chases, illicit affairs, and a notorious ring of Eastern diamond thieves all play into the plot as the book races toward its high-octane climax, and the Abels circle ever closer to the dangerous truth.