In 1999, DC and Marvel Comics did something that would seem unimaginable today and allowed Superman to crossover with Fantastic Four for a special, deluxe-sized issue written and illustrated by Dan Jurgens and Art Thibert. In it, Galactus eats Krypton and makes Superman his new Herald before he is ultimately defeated by the Fantastic Four.

The book opens with a flashback that shows the planet of Krypton exploding once again; this time, however, it's destruction is viewed by Marvel's Galactus, who creates a small capsule and sends it to earth, where a shadowy figure intercepts it before allowing it to reach its intended recipient: Superman. After defusing a terrorist's nuclear device, the pod reaches Superman and delivers his father's final message: Krypton didn't explode due to natural causes. Galactus ate it.

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Superman travels to the Fantastic Four's earth and gives them the crystal, which unleashes Hank Henshaw, the Cyborg Superman, into the FF's equipment in the Baxter Building, but before he can join forces with the planet-eater like he desires, a mysterious orb consumes the Man of Steel, and he emerges as the new Herald of Galactus. Superman attempts to resist Galactus' will, but the Power Cosmic soon consumes him, overrides his sense of identity, and sends him out into the universe to find a suitable planet for his new lord and master.

The Fantastic Four ultimately team up with Henshaw to go after Superman, and the story takes a fun break to spell out the many parallels between Henshaw and Richard's famous family. Jurgens created Hank Henshaw as an evil version of Reed Richards, and the character's backstory has always been a dark inversion of the Fantastic Four's.

While the FF went to space, were bombarded with cosmic rays, and came back as superheroes, Henshaw and his team went to space and were horribly mutated by the cosmic rays that hit them. Henshaw was his crew's only survivor and used his new cybernetic powers to become the Cyborg Superman, destroying Coast City.

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Superman found his master a new planet to devour, but when it came time for the being to feed, Superman's deep memory of Krypton's destruction revived his sense of identity, and he turned his newfound Power Cosmic against Galactus. The Devourer strikes down the Man of Steel, stripping him of his enhanced powers, but with his mind now clear, Superman helps the Fantastic Four reverse the polarity of Galactus' Elemental Converter, causing it to drain power from him instead of the planet.

With Galactus thwarted, the fantastic five defeat Henshaw after his sudden but inevitable betrayal and discover that he fabricated the message Superman discovered in the beginning of the story. Once Superman convinces Galactus to only feed on deserted planets, Reed Richards turns off the Elemental Converter and frees the Devourer, who immediately destroys Henshaw for altering his message and setting up this conflict.

Superman and the Fantastic Four return to the Baxter Building and spend a moment with Reed and Sue's son Franklin. In the Marvel Universe, apparently, Superman is a fictional character with his own animated series which Franklin faithfully watches every week. Franklin is overjoyed to get to meet his hero in real life, and the Man of Steel gives the boy his famous cape before returning to his own Earth.

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