"The Great Chieftain Cyclops" "Daishuuchou Saikuropusu" (大酋長サイクロプス ep 36
The 999 stops at an abandoned artificial colony world. Tetsuro is pleased with its appearance but Maetel is puzzled that the colony looks quite different from her last visit. They investigate further, and are set upon by a terrified mob of physically identical men. Maetel recognizes their face as being that of the colony's architect, Dr. Cyclops. She shouts for the Doctor's assistance and he quickly makes his appearance and orders his clones to withdraw. Back at his laboratory, Maetel speaks alone with her old friend and he tells her that he had taken up residence in the colony and held on despite fading health in the hope he might someday convince others to trust him and his design. Maetel replies that she trusts him, and he sighs that that was what he had been waiting to hear. He triggers the colony's self-destruct system and collapses. Maetel and Tetsuro flee to the 999, which escapes just as the colony explodes. Maetel explains that Cyclops had been ostracized by the entire galaxy when a design flaw killed all the colony's human inhabitants. She gives Tetsuro the Doctor's parting gift to him, a personal diary chronicling his long years of loneliness.