Buck Rogers in the 25th Century S01E11 - Cosmic Whiz Kid

Roderick Zale specializes in political kidnappings. His latest is eleven year old Genesian President Hieronymus Fox. Initially, Earth authorities refuse the Genesian request for help, as there are no formal treaties between Earth and Genesia. It turns out that Fox is from the twentieth century - a child genius who froze himself when he saw the calamity coming, and was looted by aliens and passed from planet to planet. Genesia wants him back, but is afraid the Earth will demand his repatriation.