Lois Lane wasn't herself... literally. "Lois" turned out to be the villain Parasite, who assumed Lois's form to get close to Superman. But in doing so, the Parasite contracted and died from Kryptonite poisoning. Worse, he took the secret of the real Lois' location to his grave!
The search for Lois taxes the Man of Steel to his very limit in this volume collecting THE ADVENTURES OF SUPERMAN #579 & 580, SUPERMAN: THE MAN OF STEEL #101 & 102, ACTION COMICS #766 & 767, SUPERMAN #158 and the lead story from SUPERMAN: METROPOLIS SECRET FILES #1.
Unfortunately, while searching for Lois, Superman is weakened by a mysterious ailment and scours Metropolis until he collapses. It then falls to Batman to conclude the search while Steel, Superboy, Supergirl, and The Atom team up and miniaturize to actually enter the Man of Steel's dying body. There, the heroes must find the cause of Superman's illness and cure him... if there's still time!
