On her eleventh birthday, Lilly's family visits the Cattail Marsh to see the newly hatched cygnets. The family outing turns tragic when Dean Drake shows up with his shotgun. Lilly sees him kill her father, injure her mother, and slaughter the bevy of trumpeter swans. The sheriff, her mother, sister, and best friend all think Lilly is trying to make sense of a senseless accident by blaming Drake. But Lilly knows the truth. Left alone she must bring him to justice.