The Lost Planet is a 1953 Columbia Pictures 15-chapter serial which has the distinction of being the last interplanetary-themed sound serial ever made. It was directed by Spencer Gordon Bennet with a screenplay by George H. Plympton and Arthur Hoerl (who also wrote for Rocky Jones, Space Ranger). It appears to have been planned as a sequel to the earlier chapterplay Captain Video: Master of the Stratosphere and shares many plot-points, props and sets, as well as some of the same cast. However, the Video Rangers do not appear, and their uniforms are instead worn by "slaves" created electronically by Reckov, the dictator of the Lost Planet (Gene Roth) with the help of mad scientist Dr. Grood (Michael Fox) and enslaved "good" scientist Professor Dorn (Forrest Taylor).

The serial is interplanetary in name only, since while Dr. Grood has a "space projectile" identical to that seen in the Captain Video serial, the other characters fly to the Lost Planet in an ordinary light aircraft! As on the Rocky Jones, Space Ranger TV series, with which it shares a writer, the dialogue is often as unintentionally hilarious as that of an Ed Wood film. Typical: "How are we going to find it, it's the Lost Planet."

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This film, Lost Planet, was produced on 4 June 1953 and fell into the public domain on 1 January 1971.