An Alien who calls himself The Watcher contacts the Fantastic Four to warn them of an incoming doom - Galactus, a unique terrifying gigantic nearly indestructible alien humanoid who devours whole planets, is coming to feed on Earth.

The Fantastic Four can't defeat Galactus, so they try to convince his slave and herald The Silver Surfer to help them somehow.

The Skrulls may have been defeated, but they want revenge, so they send a superior genetically modified Srkull - Superskrull - to take down the Fantastic Four.