Hagedorn carried out three knife murders of young boys in the forests near Eberswalde over a span of two years, with the crimes sharing a consistent method and location that ultimately helped investigators identify him. His case intersected with the legal architecture of the East German state in an unusual way: the abolition of capital punishment for juvenile offenders meant that only his final murder — committed after he turned eighteen — could carry the death sentence. He was executed in 1972 and holds a grim place in East German legal history as the last civilian put to death for ordinary criminal offenses.

As a co-founder of the Cali Cartel, he helped build what became one of the most sophisticated drug trafficking organizations in history — distinguished from its Medellín rival less by violence than by corruption, preferring to purchase politicians, judges, and law enforcement rather than kill them. At its height, the cartel was estimated to control as much as 80 percent of the world's cocaine supply. His eventual arrest and extradition to the United States marked a significant chapter in the decades-long effort to dismantle Colombian trafficking networks.

Operating in the Soviet Union, Tsiuman targeted victims based on a specific and consistent detail of their appearance, a pattern that gave investigators both a signature and a nickname that followed him into history. The compulsive specificity of his crimes placed him among a broader wave of Soviet-era serial killers whose cases remained suppressed or poorly documented under a system reluctant to acknowledge such phenomena. His two known aliases reflect how the cases registered in public memory long before formal criminal justice discourse caught up.

His 1974 plot to commandeer a commercial aircraft and crash it into the White House anticipated, in stark outline, the methods used in the September 11 attacks more than two decades later. Byck killed a police officer and a co-pilot before being shot by authorities, never getting the plane off the ground. The scheme drew little public attention at the time, but its logic — civilian aviation as a weapon against a seat of government — later gave it a grim retrospective significance.