Joe Profaci was a ruthless, deeply religious American La Cosa Nostra boss who ruled his Brooklyn crime family for over three decades, but his extreme greed and heavy taxation of his own men ultimately triggered a bloody, fractured rebellion within his ranks.

H.H. Holmes, widely regarded as one of America's first documented serial killers, infamously constructed a custom-built "Murder Castle" in Chicago to lure, torture, and execute victims during the 1893 World's Fair.

Known as the "Teflon Don" for his uncanny ability to repeatedly evade criminal conviction, John Gotti ruled New York’s powerful Gambino crime family in the late 1980s with a flamboyant, media-savvy style before finally being convicted of murder and racketeering in 1992.

John Wesley Hardin was one of the Old West’s deadliest outlaws, a notorious Texas gunslinger who claimed to have killed over 40 men before ultimately being shot in the back.

Pol Pot was the brutal dictator of the Khmer Rouge whose radical communist regime orchestrated the Cambodian genocide, resulting in the deaths of an estimated 1.5 to 2 million people through forced labor, starvation, and mass executions.

Joe Bonanno was a powerful American mafia boss who led the Bonanno crime family for over three decades, famously operating with a corporate-style approach to organized crime and becoming one of the longest-surviving, original members of the Commission.

Morton Sobell was an American engineer who was convicted of conspiracy to commit espionage in 1951 for his role as a Soviet spy alongside Julius and Ethel Rosenberg, a crime he finally admitted to in 2008.

Known as the "Highway Killer," Larry Eyler was a prolific American serial killer who stalked the Midwestern Interstate system between 1982 and 1984, brutally murdering a minimum of 21 teenage boys and young men.

Juan Corona was an infamous California labor contractor with a history of schizophrenia who was convicted in 1973 for the brutal machete murders and secret orchard burials of 25 transient farm workers.

Known as the "Hell's Belle" of midwestern serial killers, Belle Gunness lured dozens of wealthy suitors and husbands to her Indiana farm in the early 1900s, only for them to vanish alongside their fortunes.