Over a span of months in 2003 and 2004, he carried out a sustained series of killings in Seoul that targeted two distinct groups — wealthy elderly residents and women in the sex trade — a pattern that reflected calculated opportunism rather than random violence. The eventual conviction on 20 counts made him one of South Korea's most prolific convicted killers, and the investigation exposed significant gaps in how the Seoul metropolitan police coordinated responses to linked crimes.

Mullin carried out his killings in Santa Cruz County over roughly four months, driven by a delusional belief that human sacrifice could avert a catastrophic earthquake — a rationale that gave his crimes an internal logic wholly removed from conventional motive. His case became a study in how severe mental illness can interact with violence at scale, and investigators at the time were further confounded by the simultaneous activity of Edmund Kemper in the same region, two unconnected killers operating in the same area at the same time.

Her case stands out not for its scale but for its motive — a calculated act of retaliation against the very family who had constrained her personal life. Over the course of 1924, she poisoned seventeen relatives, killing three, in a campaign that unfolded quietly within a domestic circle that had no reason to expect the danger coming from within it.

His decades of quiet academic life in Vancouver stood in stark contrast to a wartime record that had earned him a life sentence in absentia — for rounding up Jews and communists in occupied Netherlands. The gap between those two lives, sustained for over forty years under a false name, is what gives this case its particular weight. It took a private Dutch investigator, not any official apparatus, to close it.

Her inclusion here rests less on documented personal crimes than on the machinery she moved through — the Borgia family's calculated use of marriage, alliance, and rumored violence to accumulate power in Renaissance Italy. Lucrezia was married three times by papal arrangement, each union serving her father's political ambitions, and at least one of her husbands may have been killed when his usefulness expired. The historical record on her own agency remains genuinely contested, which is itself part of what makes her figure endure: she inhabited a system where proximity to power and proximity to harm were difficult to separate.