Nurse Charles Cullen is one of America's most prolific serial killers. Police say he may have murdered up to 400 victims, Cullen claimed he acted mercifully. An in-depth look into the case reveals the truth behind his motives.
Nurse Charles Cullen is one of America's most prolific serial killers. Police say he may have murdered up to 400 victims, Cullen claimed he acted mercifully. An in-depth look into the case reveals the truth behind his motives.
