Alison Garland is a 14 year old schoolgirl found dead on the school grounds just after lunch. She appears to have slit her wrists and committed suicide, but there is also evidence that she had sexual relations just earlier that day. As Leo Dalton looks into the case he learns that Alison was also a school bully and was a very unhappy young woman. Harry assists the police in the stabbing death of a car dealer. The evidence suggests that he was stabbed in his garage and his body then dumped. The case takes a radical twist when they find that the knife found by Alison's body was also used to kill the car dealer. Nikki assists the police in the death of an elderly woman who appears to have been maltreated.

El equipo investiga el tiroteo sistemático de una familia que estaba de picnic junto a un río. El caso hace revivir recuerdos de la muerte de una joven junto a ese mismo río hace 10 años.