Superman arrives yet again in the 30th Century, though now with a much later roster of Legion of Superheroes members that now have to deal with Dev-Em the Daxamite who is on a destructive rampage on the moon, even activating a Dominators' weapon that will blow up the moon. Superman and the Legion manage to stop Dev-Em and the weapon's detonation timer with one second left, but as the Legion leave to bring Dev-Em to justice, the Linear Man shows up again, revealing to Superman that the moon's destruction was meant to happen and that it was the only way for Superman to return back to his own time. As Superman helplessly watches, the Linear Man resumes the weapon's countdown, destroying the moon and sending Superman back to the present time, making him wish he could return back to the 30th Century to stop the moon's destruction.

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