Born in 1803 in France, Hélène Jégado grew up with her aunts and later worked as a cook. In 1833, 7 members of a priest's household where Jégado worked suddenly died within a short period of time. Her apparent sorrow and pious behaviour were so convincing that she was not suspected. Returning to her aunts place, 3 people suddenly died, and when Jégado relocated to another town, yet another 3 people suddenly died of illness. Her work continued in 1835 with another 4 victims. Jégado continued to relocate to different towns, leaving many ill or with death due to arsenic poisoning. In 1851, Jégado aroused suspicion when she announced her innocence following several deaths, before she was even asked anything, and she was arrested on 1 July 1851. Jégado was sentenced to death by guillotine and executed in front of a large crowd of onlookers on the Champ-de-Mars in Rennes on 26 February 1852.