Superman and Supergirl have successfully achieved the destruction of Warworld. But now Superman has to track down Supergirl, wherever she has gone. She should have rejoined him for now. Superman guesses Kara's collision with Warworld knocked her unconscious and her body was going too fast to stop. Superman calculates Supergirl's flight path and flies after her, building up speed to equal the unconscious Kara's, breaking through every physical barrier he has encountered before until he leaves his universe.

Kal-El is considering to turn around because his cousin can't have traveled so far when he spots her. Superman is about to reach her when The Spectre shows up all of sudden and knocks him back into his universe.

Superman gets angry but the Spectre merely warns him that he must stop because the realm before him is one which no living mortal may enter. Unable to persuade the Spectre to let him by, Superman tries to fight his way past him, but his powers are totally ineffectual against those of the Ghostly Guardian.

Seeing Superman won't listen, the Spectre decides Kal-El must be educated about his limitations. The Spectre forces him to sit through visions of the demise of Krypton, which he's again powerless to prevent, and Death taking his father Jonathan again, which Superman is unable to stop.

Finally, the Spectre conjures up a dark version of Superman. While the doppelganger pummels Superman mercilessly, the Spectre tells it's pure, unadulterated power without conscience or remorse that can destroy him if he allows it to run amok. Superman is losing until he realizes that "evil" Superman is just a manifestation of the arrogant and headstrong attitude he has been displaying of late.

The evil Superman fades away and Superman apologizes to The Spectre. Then The Voice, the Master of the Spectre, speaks up to tell Superman that admitting his own foolishness is the first step to become truly wise.

Superman is amazed, but the Spectre explains it was the Voice who commanded him to stop Superman. Even if Superman didn't mean any harm, he was going where no living beings are allowed to go. Superman pleads with him to save his cousin, and The Spectre materializes an unconscious Supergirl in his arms, saying that all Superman had to do was ask. The Spectre hands Kara to Kal-El and departs. Superman reflects power untempered with conscience is meaningless and thanks the Spectre, but he realizes he's already gone.

Supergirl, who has been unconscious during her entire journey into the realms beyond death, wakes up right then. She asks what has happened to her, a tale Superman narrates as they head back towards Earth.