An older version of Franklin Richards travels from the future with an ominous warning for his younger sister Valeria: a conflict is approaching, a clash between four extraordinary cities. And now the Fantastic Four, humanity's premier explorers and imaginauts, launches a series of incredible adventures into four unique and bizarre lands.

Deep beneath the Earth's mantle, the remnant of a mad experiment gone awry begins to rise. From an ancient seascpae, the last descendants of a lost kingdom make contact with mankind. In the fabled Blue Area of the moon, a king girds his people for war. And in the Negative Zone, strange and deadly creatures prepare for conquest.

Thrust into the center of this conflict are Mister Fantastic, the Invisible Woman, the Human Torch and the Thing - a legendary family, a group of heroes sworn to protect humanity while expanding the limits of knowledge and adventure. Side by side with new allies and confronted with menacing foes, it's the Fantastic Four as they prepare for the War of the Four Cities!