Clive Yorkin was a career criminal; he committed numerous crimes such as robbery and murder. He was placed in solitary confinement and realized he had no chance of release so he agreed to undergo the experiment called the Nephron Process. The experiment was to try and cure him of his violent tendencies by making him associate crime with pain. Clive Yorkin’s pleasure and pain centers in his brain were reversed, so the sent him insane. Yorkin escaped, and was next found near the dead body of Iris Allen. The Police believed Yorkin to be her murderer until security camera showed that he had only witnessed her death at the hands of Reverse-Flash.
The Nephron Process gave Yorkin the ability to drain life energy from other people through touch. For a whole day he terrorized the city with his new ability. A teenaged psychic helped track him down and brought the Flash in to help. The Flash then defeated Yorkin, who he trapped in a sinkhole.
Yorkin was recently revealed to be alive and imprisoned in Iron Heights.