The fort where much of the episode takes place was located near Vasquez Rocks, a geological formation north of Los Angeles; its distinctive 45-degree angle spire can be seen in the distance of a number of shots. Screen Gems Productions built the fort for Tales of the 77th Bengal Lancers (1956). The fort (and Vasquez Rocks) also showed up in other television productions during the 1960s, including Bonanza (1959), Mission: Impossible (1966), and Star Trek (1966). When Vasquez Rocks was purchased by Los Angeles County for a park, the fort was demolished; the parking lot occupies the area where the fort once stood.
Anna says that her father worked under Joseph Lister and mentions the germ theory of disease. Lister began publishing his papers on antiseptic practice of medicine in 1867 and achieved fame for his practices within a couple more years, lecturing to large audiences. In 1879, Listerine mouthwash was named after him. His name also was given to the bacteria genus Listeria.