Serial killer who murdered hospital patients and kept his crimes a secret for over 17 years.
He started working in hospitals at age 18 as an orderly.
He acquired the nickname "Angel of Death" while working in hospitals because he always seemed to be around when a patient died.
He lived with his lover Carl Hoeweler, whom he suspected of cheating so he poisoned him to keep him from leaving their apartment.
He claimed to kill people to ease their suffering, not unlike Jack Kevorkian, who believed in assisted suicide.