When an experimental space voyage goes awry, four people (Fantastic Four) are changed by cosmic rays. Scientist Reed Richards gains the ability to stretch his body into various contortions, and takes the name Mr. Fantastic. His wife, Sue Richards, receives the power to turn invisible and create force fields, calling herself the Invisible Woman. Her younger brother, Johnny Storm, gains the ability to control fire, becoming the Human Torch. And pilot Ben Grimm is turned into a super-strong rock creature calling himself Thing. Together, they use their unique powers to help the world battle multiple threats, and to foil the evil plans of their equally powerful enemy, Doctor Doom.