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Although the abrupt ending clearly hints at a sequel that would end Jason's voyage, one was never made. No clear reason has ever been given, but it is presumed to be a combination of factors. The movie was a box-office disappointment - though not a failure - at the time, and special effects creator Ray Harryhausen's love for ancient spectacle was going out of fashion with young 1960s audiences. By the time the movie became a cult phenomenon, Harryhausen was too busy working on the sequels to The 7th Voyage of Sinbad (1958), so the Jason sequel died a quiet death.
It took Ray Harryhausen four months to produce the skeleton scene which runs, at most, three minutes.
While filming footage of the Argo off the coast of Italy, a replica of the Golden Hind sailed into view. Sir Francis Drake (1961) happened to be filming in the same location. Producer Charles H. Schneer shouted, "Get that ship out of here! You're in the wrong century!" dispelling any tensions that arose from both shots being lost.
After Ray Harryhausen received the Gordon E. Sawyer Award recognizing his contributions to the film industry at the Oscars' Science & Technical Ceremony in 1992, Tom Hanks, the host of the event, said "Some people say Citizen Kane (1941) or Casablanca (1942). I say 'Jason and the Argonauts' is the greatest movie ever made."
Talos was changed into a living bronze giant after the success of Sergio Leone's The Colossus of Rhodes (1961). It would become one of Ray Harryhausen's most famous creations.