Over nearly three decades, Doss killed steadily and without apparent detection, moving through marriages and family relationships while poisoning those closest to her. The span of victims — husbands, grandchildren, a sister, a mother — reflects a pattern that operated entirely within domestic life, which is partly what allowed it to continue as long as it did. Her case drew significant public attention not only for the scale of the killing but for the contrast between her demeanor and the gravity of what she had done.

Over the course of a single year, Ritchie killed five people across Anchorage's parks and trail systems, targeting victims in the late-night hours with a consistency that suggested deliberate method. The outdoor public spaces he chose — ordinarily associated with recreation and transit — became sites of vulnerability for those moving through them after dark. His killing spree ended only when he was shot by police in November 2016, weeks after his final murder.

Wallace operated within his own social network — targeting women he knew through work, family connections, and mutual acquaintances — which allowed him to evade suspicion for years while attending the funerals of his victims and even filing missing persons reports. His crimes unfolded over four years in the Charlotte area before investigators connected the killings, a delay that drew significant scrutiny toward law enforcement's response to a series of murders affecting predominantly Black women.

Operating without medical credentials in a small Maharashtra town, Pol exploited the trust placed in healthcare workers to carry out killings spanning more than a decade. The use of succinylcholine — a paralytic agent that can mimic natural death — made the crimes difficult to detect and allowed him to continue undetected across six victims. His case sits within a broader pattern of medical imposture turned lethal, where the social authority of the doctor role provided both access and cover.

What brought Stafford to justice was a pair of mass killings in 1978 — a family of three ambushed on an Oklahoma highway, followed days later by the execution-style murders of six fast-food workers — but the full scope of what his wife alleged extended across seven states and three dozen victims. He was convicted, sentenced to death, and executed in 1995, having never admitted to any of it.