Ben Haddon invents a device that makes everyone in Central City forget that the Flash ever existed!
A little girl, Alice, accidentally drops her doll into the river. The Flash retrieves Alice's doll, earning her undying gratitude. A research scientist, Ben Hadden, bathes his cat in a strange radiation. When the housekeeper, Mrs. Prentiss, arrives, with a saucer of milk for the cat, she becomes confused. Prentiss no longer has any recollection of Hadden's cat, or, in fact, that he ever had one. Arriving at police headquarters, the Flash is baffled at the desk sergeant's complete lack of recognition of him. On the street, parolee David Gulch walks right past the Flash, despite an earlier threat to get even with him. It is at this moment that the Flash notices that he is becoming transparent. The Flash races to the newspaper office of Picture News reporter, Iris West.
Astonishingly, West, too has no memory of ever encountering the Flash. Overhearing a police officer responding to a robbery, the Flash sets aside his problem, to thwart the crime. It takes every last vestige of the Flash's will power to maintain his corporeality. By the time he reaches the scene of the crime, the Flash's body is all but vapor. Anticipating the Flash's intervention, Haddon, the thief, literally blows the Flash's body back to his secret lair. Haddon reveals that he spread a specific type of radiation across Central City, causing the populace to forget the Flash ever existed. Inexplicably, this loss of belief in the Flash is causing the Flash to fade from reality. Haddon exposes himself to the radiation, to sever the Flash's sole remaining tie to reality.
The Flash, though, doesn't completely fade away, as Haddon expected. Alice's great belief in the Flash is just strong enough to tether the Scarlet Speedster to the material world. The Flash seeks out Alice, finding her at the waterfront. The nearer the Flash approaches to Alice, the more corporeal he becomes. As he moves away from her, however, he begins to fade again. With Alice by his side, the Flash writes a letter to every single person in Central City, begging them to believe in him. The populace complies, restoring the Flash to normal. The Flash travels to the island nation of Bora Balu to bring Haddon to justice. Alice's steadfast belief in the Flash garners her fame and fortune, ensuring her a prosperous future.
The Flash is summoned to Central City Penitentiary. Upon arrival, the Flash is asked to speak with his arch-nemesis, Abra Kadabra. Though the man in Abra Kadabra's cell looks and sounds exactly like Abra Kadabra, he is really Slor Disi. A police officer from the 64th century, Disi was telepathically summoned by Abra Kadabra. Believing that Abra Kadabra wished to return to his own century, Disi was sent back to collect Abra Kadabra. Disi was immediately knocked unconscious.
Abra Kadabra used Disi's future technology to exchange their appearances, then escape. The Flash leaves Disi in Abra Kadabra's cell, until he can investigate Disi's claims. The Flash decides to look for Abra Kadabra at an International Magician's Convention. Sure enough, Abra Kadabra, still appearing as Disi, is there, already on the stage. As the Flash closes in on Abra Kadabra, his uniform is suddenly torn from his body. The Flash accelerates his vibratory rate to blur his features, protecting his secret identity.
Abra Kadabra counters by using a numbing force to slow the Flash down. Acting quickly, the Flash disguises himself in the garb of the famous stage magicians, displayed in the theater. Moving in and out of one disguise after the next, the Flash confuses Abra Kadabra into firing on the wrong uniform. Once the Flash delivers the knockout blow, Abra Kadabra is turned over to Disi. The 64th century lawman vows that Abra Kadabra will never trouble the Flash, or his century, ever again.