The 6th Target- James Patterson, paperback

The Women's Murder Club faces its most terrifying — and personal -case ever. A burst of gunfire leaves several people dead-and a member of the Women's Murder Club fighting for her life. Detective Lindsay Boxer pursues one lead after another to capture her friend's attacker... but the clues don't seem to make sense. While Assistant District Attorney Yuki Castellano prepares to prosecute a high-profile trial, San Francisco is in the grip of a chilling crime spree. Children of wealthy families are being abducted. But the kidnappers follow with devastating silence-no message, no ransom demand. Now with the entire city plunged into fear, Lindsay must frantically work to connect these horrific crimes.