A male nurse who was convicted of killing patients in Germany with overdoses of heart medication is now believed to have killed at least 84 people.

A pastor prayed over Elizabeth Wettlaufer and told her not to kill again. A lawyer advised the registered nurse to take her murderous secrets to her grave. A Narcotics Anonymous sponsor dismissed her insinuations of harming seniors as the talk of a "pathological liar," while an ex-boyfriend attributed her confessions of killing nursing home patients to a "psychiatric episode."

A Western University criminology professor says Elizabeth Wettlaufer fits the description of a serial killer.