The Flash finds murderer, Clive Yorkin, undergoing the Nephron Process. Yorkin, clearly insane, keeps depressing the pain button, inflicting agonizing trauma to his brain. When the Flash attempts to remove Yorkin from the machine, Yorkin, in a rage, attacks the Flash. The Flash is taken aback by Yorkin's super-human strength, an apparent side effect of the Nephron Process. The Flash vibrates his molecules, at super-human speed, to wrench himself free of Yorkin's crushing grip.
Impossibly, Yorkin is able to vibrate in sync with the Flash. Yorkin hurls the Flash through the floor, where he falls five floors, to the basement. Doctor Gilbert Nephron confronts Yorkin. By the time the Flash returns, two prison guards have been rendered unconscious, and Yorkin has fled. Left behind is Nephron, strapped into his own machine, with both the pain and pleasure centers of his brain being overstimulated simultaneously. The overload has left Nephron a vegetable.
The Flash follows Yorkin's path of destruction to an open manhole grate. Yorkin has escaped through the sewers. The next morning, the Flash, as police forensics scientist, Barry Allen, meets with the Chief of Police, Harvey Paulson. Allen is introduced to Detective Frank Curtis, an undercover narcotics officer. Heroin is being moved from the evidence room through Allen's laboratory, and back out onto the street. Allen and Curtis are asked to investigate the matter.
Curtis has already tracked down the smugglers' base of operations. Fearing a large police presence would tip off the dirty cops in the department, Curtis and Allen opt to do the bust themselves. Unbeknownst to them, their conversation is eavesdropped upon by a shady character, who informs the smugglers of their intent. Allen and Curtis storm the smugglers' warehouse, only to find it empty. It's a trap. Gunmen fire on Allen and Curtis from the shadows.
Allen is hit, but vibrates his molecular structure, at super-human speed, to intangibility, allowing the bullets to pass harmlessly through him. Curtis tells Allen to run, while he attempts to take out the car pursuing them. Allen pretends to let the car hit him. Underneath the car, Allen switches into his Flash costume. The Flash gets Curtis to safety, before taking out the hoods in the car. The Flash "departs", just as Allen rejoins Curtis. A mysterious woman, named Melanie, uses her psychic bond with the Flash to forcible draw him to her. Yorkin finds his way to Allen's home, and peers through the window at Allen's wife, PIcture News reporter, Iris West.