Mary Ann Cotton, born in East Rainton, was Britain's most prolific murderess. In Cornwall, Seaham, Walbottle and West Auckland, she dispatched at least 14 persons, including three husbands, poisoned for their insurance money. Other victims included her own children, step-children, a lover and a friend. Her fourth, bigamous marriage, was to Frederick Cotton at St Andrew's church in Newcastle.
The Cottons moved to West Auckland, where they lived in Johnson Terrace (demolished) and latterly at 13 Front Terrace. Between 1871-2, four more fell victim to 'gastric fever'. A final arsenical poisoning of a burdensome step-son blocking the way to her fifth marriage, proved one too many. The body revealed abnormal traces of arsenic and the four previous victims were exhumed; all showed similar evidence of poisoning. Mary Ann was tried at Durham Assizes and executed at Durham Jail..
Arthur Conan Doyle saw Mary's effigy in the Madame Tussaud's chamber of horrors, then located in Baker Street. The guide read:

'The series of cold-blooded murders for which this wretch was hanged on the morning of Monday 24 March 1873, are crimes... which no punishment in history can atone for. The child she rocked on her knees today was poisoned tomorrow. Most of her murders were committed for petty gain; and she killed off her husbands and children with the unconcern of a farm-girl killing poultry.'