Invasion: First Strike!

In the latest company-wide DC crossover (and the last for a couple years), an armada of aliens assembled by the Dominators (a Legion of Super-heroes enemy appearing here in the present-day DC universe for the first time) attack Earth.  At the same time in publication history, Batman suffers a devastating Death in the Family.

Superman #26

Superman and the SCU investigate another inexplicable murder with a voodoo doll left at the crime scene.  Although Superman is growing noticeably more fatigued (which he blames on his recent encounter with Braniac), he defies the U.S. military's commands and rushes to stop an invasion of Thanagarian hawk men.  While fighting in the skies, our hidden villain Baron Sunday sticks a pin in a Superman voodoo doll and he falls from the skies, disappearing from the battle.  Captain Atom tries to find the missing Superman and runs into the Guardian instead.  Scanning the city at Lexcorp tower, even Braniac can't seem to locate the Man of Steel.  Once again, Gangbuster succeeds where Superman failed: he tracks down Baron Sunday and defeats him with near super-human strength.  After disposing of the villain, he runs off on the rooftops, wishing his head would stop buzzing.  Meanwhile, at the ruins of the Daily Planet, Jimmy Olsen is desperately trying to call Superman with his signal watch.

Adventures of Superman #449

In Superman's absence, the Guardian patrols Suicide Slum and tracks down Gangbuster.   The Newsboy Legion (also re-introduced in Superman Annual #2) tries to help Guardian by ramming his car into Gangbuster while they fight, but they drive it into the river.  Superman resurfaces (literally) to save them from the water, the first he's been seen since his disappearance.  Amanda McCoy, the Lexcorp employee from back in Superman #2 who tried to tell Lex Luthor that Clark Kent was Superman is revealed to be the woman who's spying on both of them to prove her hypothesis.  Captain Atom finally finds Superman and, painfully reminding him that he's not really human, picks him to go to the Dominators to negotiate a cease-fire, which works for the moment.  To be continued in the pages of Invasion #2: Battleground Earth.  The conclusion of Invasion would mark a dramatic turning-point in post-Crisis Superman history.