Originally intended to be a story featured in the TV series Amazing Stories (1985). Steven Spielberg liked the idea so much he decided to make it a theatrical release.
The black-and-white photos of Frank and Faye used in the opening credits were real-life photos of Hume Cronyn and Jessica Tandy, who were married for decades.
After this movie, Jessica Tandy and Hume Cronyn would appear in only three more movies together. Their last film, Camilla (1994), was released two months after her passing.
A horror film was going to be titled Batteries Not Included, but was forced change its name when this film was being written. That movie turned out to be "Child's Play".
The jazz music heard at different points throughout the movie can also be heard in "Cocoon: The Return (1988)," which also star Hume Cronyn and Jessica Tandy.