Flash faces off against Mirror Master, Captain Boomerang, the Top, Pied Piper and Captain Cold. And Barry reveals his secret identity to Iris.
Sam Scudder, the notorious Mirror Master, sits in his prison cell, polishing a shaving mirror. Suddenly an image appears in the looking glass, of a parallel world, one where the Flash is a super-villain, and the Mirror Master is the hero of Central City. Of particular interest to Scudder, is the mirror weapon his parallel counterpart uses, to subdue the evil Flash. Scudder uses his mastery of mirrors to teleport out of his cell, using the sun's rays reflected on the shaving mirror. Certain that his counterpart's mirror weapon is the key to finally destroying the Flash, Scudder builds an exact replica of it.
Wanting to share his triumph, Scudder, as the Mirror Master, sets about to freeing the rest of the Flash's Rogues' Gallery. Inspired by a method last used by the super-gorilla, Grodd, the Mirror Master uses a special mirror to exchange the places of the rogues with innocent civilians, freeing them all from prison. Holding court over the Rogues, the Mirror Master explains his surefire method for destroying the Flash. Meanwhile, Police forensic scientist, Barry Allen, and his wife, Picture News reporter, Iris West, make plans to celebrate their one-year wedding anniversary.
Allen intends to reveal his secret identity, as the Flash, to his wife, at their lunch date. Allen overhears a police broadcast regarding a crime being committed by the Rogues. Allen heads out to confront the Rogues, as the Flash. The Flash is surprised to find the Rogues seemingly waiting for him to arrive. The Mirror Master unleashes his new weapon, which completely fails to have any effect on the Flash. The Flash is seconds away from defeating the Rogues, when Captain Cold lays down an ice sheath across the floor. Unable to slow his momentum, the Flash skids into the wall, knocking himself out.
The Rogues take the opportunity to flee. In the interest of discovering what went wrong, the Mirror Master enters the mirror world. The Mirror Master seeks out the evil Flash, and releases him from prison. The Mirror Master then warns his heroic counterpart that the Flash is on the loose. The Mirror Master observes as his counterpart, once again, subdues the Flash. Understanding better how the mirror weapon works, the Mirror Master returns to his world. The Rogues throw down the gauntlet. The Flash races to confront the Rogues, and falls prey to the Mirror Master's mirror weapon.
In reality, though, the Flash that confronts the Rogues is the evil Flash from the parallel dimension. Having gotten ahold of the Mirror Master's body swapping mirror, the evil parallel Flash has exchanged places with his heroic counterpart. The Flash's super-speed is stolen by the Mirror Master's mirror weapon, allowing the other Rogues to bring their weapons to bear on their "old foe". Meanwhile, the Flash determines that his teleportation into his counterparts's cell has weakened it's defenses. Escaping through the wall he came through, the Flash tracks the energy signature of the body swapping mirror back to his own reality.
Seeing the Rogues about to murder the evil Flash, the Flash barrels through them, allowing the sonic boom that follows in his wake to render them all unconscious. The Flash turns all the Rogues over to the proper authorities, as well as returning his evil dopppelganger to his proper dimension. At lunch, the Flash, as Allen, reveals his secret identity to West. Allen is stunned to learn that West has known since their wedding night, as Allen talks about his adventures as the Flash, in his sleep.