Originally intended as a vehicle for Samantha Eggar and Anthony Newley, who had starred together the previous year in L'Extravagant docteur Dolittle (1967).
Universal spent $100,000 for the rights in August 1964.
The bicycle tape seen in the hardware store is the forerunner of duct tape. Levels are still used today (2022), as are plungers and the WD-40 briefly viewed.
Among the futuristic items showcased at the Signposts of the 70's exhibition are a drawing of the soon to be launched supersonic Concorde airplane (1969), a building resembling what would be known as the Transamerica Pyramid in San Francisco (1969) and a curious round object that looked like a model for the whimsical Panasonic Toot A Loop transistor radio (1970's).
Turning to salt is a reference to the Biblical take of Lot's wife being transformed into a pillar of salt because she defied an order from God not to turn around.