The Lost Child, Part 1

When the half-naked body of a 12-year-old is discovered floating in a drainage ditch near his school, the team is called in, bringing Nikki back in contact with one of her former teachers, Noel Hopkins, now headmaster.

During Harry's preliminary examination they find clear signs of abuse, and when the police discover the victim was last seen with another boy, Liam, who has also gone missing, they fear he may have been abducted. Liam is still out there, the hope is that he is still alive, and the team, under increasing pressure from the police, must find clues from the dead boy's body in order to save the living.