19 of the Most Cruel Female Serial Killers That Have Walked on This Earth

BEVERLEY ALLITT was a regular nurse or so everyone thought, working at Grantham and Kesteven Hospital in the UK.  That was until she went on a spree between February and April of 1991.  For no valid or invalid reason she successfully killed 4 children, attempted to murder 3 more, and caused serious bodily harm to 6 more.  Her chosen method of murder was injecting the children lethal doses of insulin, or injecting air bubbles into their veins.