At a charity event organized by Iris West, the Flash performs super-speed tricks to entertain the children there as the scheduled magician has not come. Recreating a rope climbing trick, the Flash begins vibrating his molecules when he suddenly disappears from the stage. He finds himself outside near an unfamiliar city, which he discovers to be Keystone City, the home of the Golden Age Flash. Keystone City is located on Earth-Two (not named as such in this story), an Earth in a parallel universe. On Barry Allen's world, the Golden Age Flash is thought to be a fictional comic book character. Barry looks up Jay Garrick in the phone book and introduces himself to the older speedster. On this Earth, Jay had retired as the Flash years earlier, the year his comic book series was canceled on Earth-One, and married his longtime girlfriend, Joan Williams. Barry claims Gardner Fox's thoughts must have been tuned in to the events of Earth-Two.
Garrick says he is preparing to resume being the Flash and describes for Barry three incredible crimes that were committed recently. These thefts were perpetrated by three of Jay's former adversaries, the Fiddler, the Shade, and the Thinker, who have recently joined forces. The Flashes split up, with Jay taking on the Thinker and Barry against the Shade, but they are unable to defeat them. The Flashes regroup and go after the Fiddler together, saving a man from a falling steel girder along the way.
Shade and Thinker meet up and realize that there are two Flashes. They hurry to warn the Fiddler of this turn of events, but the Fiddler has already managed to stop the Flashes with his musical powers. He commands the two speedsters to commit robberies for him. Just as the villainous trio are about to flee with their loot, the two Flashes capture them. It turns out that they had put small jewels in their ears to block the Fiddler's mind-control music after he told them to put them down and take larger jewels, then played along in order to fool the criminals. Barry returns to his Earth after Jay announces he is coming out of retirement and will continue as the Flash of his world.