When astronaut Joseph Reardon accidentally travels through a time warp, he lands on a devastated Earth in 2148 A.D. He stumbles upon a mutant called Andro who explains that an ambitious scientist called Bertram Cabot Jr. developed a bacterium that caused a biological disaster and turned mankind into infertile mutants. Reardon decides to bring Andro to 1963 to warn the authorities and prevent the disaster; however, Reardom feels he is dying after crossing the time warp and asks Andro to kill Cabot, then vanishes, and Andro lands alone on Earth. Using hypnotic suggestion to have normal appearance, Andro goes to a boarding house seeking out Bertram Cabot Jr., but after meeting young Noelle Anderson, he learns that she is Bertram Cabot's girlfriend and Bertram Cabot Jr. has not yet been born. What will Andro do to save mankind?
—Claudio Carvalho, Rio de Janeiro, Brazil