Robby the Robot's appearance in the film was partly because it was so expensive to build him for Forbidden Planet (1956) that MGM felt obliged to use him in another project.
There is a connection with the film and Forbidden Planet (1956) when Timmie discovers a photo from the future, dated March 26, 2309, showing the return of the C57D spacecraft landing at Chicago Spaceport. The photo has his uncle in the photo, which would suggest time travel. Timmie says the photo was taken over three hundred years from now, which would explain how Robby the Robot has come to the 1950s.
As of September 2020, Richard Eyer is the last surviving cast member of this film.
The film is included as an extra on both the 50th anniversary DVD release and the 2010 Blu-Ray release of Forbidden Planet (1956).