Shadowplay: Part 2 (S04E12)

Certain now that the Shepherd exists, the team needs to find out why he is targeting the patients of the psychiatrist who alerted them to his existence in the first place. Could the doctor be the Shepherd? But as the team gets close to solving the case, Mel falls victim to one of the disturbed young women - a painful and tragic reminder never to underestimate the dangers of the job. (iTunes)