It might help to read GONE by Lisa Gardner first. In that book, SWAT team member Bobby Dodge sends the bullet that kills Catherine Gagnon's estranged husband, and sets an entire chain of events off--including Bobby's investigation by the MA State Police and becoming involved with the widowed Catherine. In HIDE, Catherine (living in AZ) makes a cameo appearance, and Bobby's ex-wife asks him to help the Boston Police Department to find out who created an underground chamber that's been unearthed at the abandoned MA State Mental Hospital. Inside the chamber are the remains of 6 young girls, wrapped in plastic bags that are approximately 30 years old. Tied into the case is an estranged witness...who recognizes her own name on a locket that's discovered on one of the young victims. I thought this book was excellent and had a difficult time putting it down. I just couldn't wait to see how everything would tie together in the end. WOW!