Brenna Scott and her boss Jett Culpepper run a search and rescue dog team and are asked to find a missing child.  Brenna finds the kidnapper as he tosses the child into a rushing river and flees.  Brenna and her dog jump into the currents and rescue the child.  Details of this abduction match two unsolved F.B.I. cold cases.  They realize that a serial child killer is on the loose. The killer emails Brenna with cryptic clues on future kidnappings.  Another child disappears.  The search and rescue team goes to the crime scene but no child is found.  The killer has given Brenna false clues.  A third child is reported missing.  Brenna realizes that she might have the key to solving these crimes but... who is this killer, why is he killing and what is his relationship to her? Can she unravel the clues and capture him before another child is taken?