Arkham

The regularly scheduled programming is interrupted for the next two months with a departure into an alternate reality.  This was similar to the X-Men's Age of Apocalypse story a few years earlier, in which a villain remakes reality in their twisted image, although this story was less serious in tone.  Arkham gave the creators a chance to re-introduce whimsical concepts from the Silver Age, like the backwards-speaking, mirror image Bizarro.  Just like Age of Apocalypse, some of these characters would carry over even after reality returns back to normal.

Superman #160

The story opens when Superman, wearing a black costume, breaks out of his chains and escapes from Arkham Asylum.  In a scene that apparently plays out every night like Pinky and the Brain, Superman is caught by Bizarro #1 and taken back to Arkham where he will inevitably escape again the following night.  Superman has no memory of the real world, and it appears neither does anybody else.

In this world gone mad, Superman is accused of killing Lex Luthor, and in his place Lois Lane (bald and wearing a different wig every night) runs Lane Corp from Lane Tower.  Jimmy Olsen is Gravedigger Lad, Bizarro's pal and caretaker of the Graveyard of Solitude.  Also every night, a Golden Age Mr. Mxyzptlk tries to get Superman's attention but is foiled by some cartoony device, like getting run over by a train in this case or having a safe fall on him in the next issue.  And every night ends with a mysterious, excruciating scream that can be heard by everyone.  All the covers this month are by Ed McGuiness, and showcase that issues featured hero opposite one of the new villains on a playing card.

Adventures of Superman #582

The Earth-born angel Supergirl finds herself as Niece Matrix, a novice in a religious order that seems to worship Alfred E. Newman of Mad Magazine.  When her angelic fire powers start to manifest, the Prankster is called in to perform a wacky exorcism, but she takes the form of an angel with fiery wings and flies away.

When Superman escapes from Arkham that night, Bizarro's JLA assembles to stop him.  It's members include a familiar face like Poison Ivy, and new characters like the monstrous machine Ignition, the fire-based Scorch, the hideous seductress Georgeous Gilly, and some others who are never seen again after this story.

Intrigued by her encounter with Superman last issue, Lois Lane shelters the fugitive Man of Steel to find out why she's drawn to him.  Superman doesn't know why, but he's drawn to Lois too.  They spontaneously kiss, but then she angrily pushes him away.  This story ends when Jimmy Olsen is transformed into a giant Turtle Boy and swallows Superman whole.

While J.M. DeMatteis' writing would tend to be New Agey, artist Mike Miller liked to hide Christian Easter eggs on his pages, so the safe that lands on Mr. Mxyzptlk reads "Calvary: Safe for Eternity" on the door.

Superman: The Man of Steel #104

Having passed through the Turtle Boy's digestive tract, Superman finds himself back at Arkham.  There, he meets a fellow inmate, John Henry Irons, who has been made to believe he's insane because he understands science.  Superman starts to think they're not crazy, only the world around them is, so he takes John Henry with him when he breaks out again.  While on the run, they find a statue in a park that's actually Steel's armor, which John Henry feels compelled to try on.

Steel and Superman are pursued by the gun-slinging Bounty and Bizarro.  Steel bashes Bizarro with his hammer, throwing him into a building that topples the buildings behind it like dominoes.  The last building lands on a train that was about to hit Mr. Mxyzptlk, giving him enough time to finally get Superman's attention to tell him all the answers can be found at the JLA headquarters on the moon.  This issue ends with another blood-curdling scream, but Superman is not taken back to Arkham.

Action Comics #769

Superboy hates his life working a fast food job until Bizarro's JLA destroy the restaurant in a fight, setting him free to start to discover who he really is.  

While most of the JLA is on Earth, Superman and Steel attack the Watchtower and get past Ignition and Georgeous Gilly.  The pair are able to resist Gilly as long as they don't look at her, but Ignition proves to be a more intimidating and formidable opponent.

When Superman gets inside, he finds a modern-looking Mr. Mxyzptlk sitting there like he's the final boss.  Mr. Mxyzptlk magically restores Superman's memory and says his name backwards, but the world doesn't return to normal like Superman thought it would.  The 5th dimensional imp points to the Earth through the window and then Superman realizes the villain who really re-made the world in his crazy image is the Joker!

This was one of the most fun months of Superman comics ever.  At the time, DC was able to keep the reveal of the villain a secret until this issue was on the stands.  Even though the next issue is titled Emperor Joker #1, it was solicited as "Emperor ?????"  Publishers truly being able to keep secrets until the book came out was part of the fun of serialized comics that has been pretty much spoiled by the internet today.