When radio presenter Anna Graves and her daughter are attacked on the beach by a crazed teenager, Anna reacts instinctively to protect her baby. But her life falls apart when the schoolboy dies from his injuries. The police believe Anna's story, until the autopsy reveals something more sinister. The evidence seems to connect Anna to a decades-old serial murder case. Is she really as innocent as she claims? And is killing ever justified, if it saves a child's life?