
World's Most Evil Killers delves straight into the stories of the world's most prolific killers. Each episode focuses on one notorious killer and features first-hand accounts of their behavior; such killers range from Fred and Rose West, Ed Gein, the Clown Killer, to the Milwaukee Cannibal. Accounts are also given by detectives who ran the cases, journalists who reported on them, relatives, experts on analysis, and sometimes even survivors.

Over four months during the late-70s, a killing duo terrorized LA by killing and dumping the bodies of ten women and girls as young as 12 on the city hillsides.

In the late 1980s, Bill Suff, aka the Riverside Prostitute Killer, is a model employee during the day, but, by night, he is a monster who lures sex workers into his van, where he stabs, strangles and mutilates them before dumping their bodies.

In December 1998, The Railroad Killer, 38-year-old Angel Reséndiz brutally beat Dr. Claudia Benton to death in her own home; he's suspected of murdering at least nine more people; he evades authorities by using a multitude of aliases.

Robert Benjamin Rhoades, also known as The Truck Stop Killer, is an American serial killer and rapist.