Harold Shipman, also known as “Dr. Death,” is believed to have killed at least 218 patients, although the total is quite likely closer to 250. This doctor practiced in London and between 1972 and 1998 worked in two difference offices, killing all the while. He wasn’t caught until a red flag was raised by several people, including an undertaker who was surprised by the sheer number of cremation certificates Shipman was a part of, along with the fact that most of the cases were elderly women found to have died in bed not at night but rather during the day. Police mishandled the investigation, and Shipman kept killing until he got greedy and tried to concoct a will for a victim that named him beneficiary, which led the victim’s daughter to become suspicious. He was finally convicted in 2000 and committed suicide while in prison in 2004.