Sergeant Gempp was a soldier in the National People's Army of East Germany in the 20th century. In the year 1974, he served under Corporal Erich Kilheffer as a border guard at Brandenburg Gate in East Berlin. After Gary Seven and Roberta Lincoln escaped, Gempp reported to Kilheffer that they had found a disoriented man near the Soviet embassy. Kilheffer declared that the man was a spy and arrested him. (TOS - The Eugenics Wars novel: The Rise and Fall of Khan Noonien Singh, Volume 1)