Miyuki Ishikawi
Here’s one to end on – and really give you nightmares. Ishikawa was a midwife working for a local hospital in her native Japan immediately after the Second World War, during the baby boom. With maternity wards overflowing, and many parents too poor to provide a proper upbringing for their children, Ishikawa decided on her own solution: she deliberately caused many of the infants to die, by starvation or lack of care. After their deaths, the midwife hid their corpses all over the city. By the time she was caught, she had killed at least 103 babies, but some officials put the real figure at closer to 169.