In an episode viewed through the eyes of DI Dunlop and Sgt Karen Mulcahy, increasingly it appears that Amber's missing mobile phone may provide a definitive answer to the mystery and that a man called Charlie may have that answer.

Unlike his wife, Ben Bailey refuses to give up hope that Amber is still alive. Following an encounter with one of her friends, he becomes convinced that his daughter was befriended by an online predator and abducted. This sets him off on a new and very dangerous course.