When a preview of this film was shown, a questionnaire was distributed among the viewers asking what scene they liked. One person answered, "The scene where Robert Taylor saved Deborah Kerr from the fire." This was in reference to the fact that much of the stock footage used in the film came from Quo Vadis (1951).
Although the prior year's The Time Machine (1960) was a big hit for George Pal, MGM gave him a tiny budget for this picture, hence the many shortcuts and footage used from other films. Russell Garcia, who scored the film, recycled themes from "The Time Machine"--even going so far as reusing entire cues from the earlier film. Additionally, William Tuttle, the makeup artist, had a considerable amount of blue body paint leftover from "Time Machine" as well: it may be noted that Neptune (who appears to Demetrios in a hallucination) is the same shade of blue as the Morlocks.
George Pal was unhappy with the script but was forced to begin production before it had been polished due to an impending writers' strike. The strike occurred during production, which stopped any rewrites.
In addition to his credited narration, Paul Frees, without additional credit, dubbed the voices of three actors: An unknown appearing briefly as a messenger, and both Wolfe Barzell and Edgar Stehli, who played the fathers of the hero and heroine respectively.
Several scenes of the principal actors on palace steps were shot at the Three Musketeers Court set on MGM's Lot Two. And the climactic scenes with the crystal ray machine utilized the famous "Kismet" steps on MGM's Lot Three, which also appeared in Pal's "The Time Machine".
George Pal had wanted to do a film about Atlantis in the mid-1950s after reading a copy of the 1949 play "Atalanta, a Story of Atlantis" by Sir Gerald Hargreaves. Pal's studio at the time, Paramount, turned down the project.
One of the factors that led to MGM's green-lighting of this production was the recent success of the U.S. release of Pietro Francisci's Le fatiche di Ercole (1958) (US title: "Hercules"). This began the cycle of spectacle films about Greek and Roman mythological heroes.