What Are Little Girls Made Of? (Episode)
Nurse Chapel's long-lost fiancé is found—along with his androids.
The Enterprise arrives at planet Exo III to learn the fate of Dr. Roger Korby, the "Pasteur of archaeological medicine." On board is Nurse Christine Chapel, Korby's fiancée, who has given up a bioresearch career on Earth to find him.
Korby contacts the Enterprise and confirms that he is living in underground caverns discovered while suffering from severe frostbite five years earlier. At his request, only Captain Kirk and Chapel beam down. The doctor shows them ancient machines left behind by the long-dead Exoites—the "Old Ones"—which Korby used to create android duplicates of his dead associates, Dr. Brown and Andrea.
Korby fashions an android duplicate of Kirk, intending to capture the Enterprise and "seed" the universe with androids. But Kirk plants false memories in his duplicate's brain—and Spock realizes something is wrong. Kirk then turns the androids against Korby, who, now aware that his own android body has made him more machine than man, embraces Andrea and fires a stolen Phaser between them, killing them both. Spock arrives with a landing party moments later; Nurse Chapel announces that she is staying with the Enterprise.