Flash Gordon's Trip to Mars is a 1938 film serial of 15 episodes, based on the comic strip Flash Gordon. It is the second of three Flash Gordon serials made between 1936 and 1940, coming between Flash Gordon and Flash Gordon Conquers the Universe. This serial has more of a plot than the others, which are episodic. It stars Buster Crabbe as Flash Gordon and Charles Middleton as the alien dictator Ming the Merciless.
Its first episode picks up where the first left off, with Flash, Dale Arden and Zarkov returning to Earth and landing in the U.S. in a farmer's field. They are fêted worldwide. But shortly they discover that another crisis is striking the Earth: a fictional chemical element, whimsically called Nitron, which is necessary to life, is vanishing from the atmosphere. Flash takes Zarkov up in an airplane to take measurements only to discover that a beam from another planet is the means aliens are using to drawing it away. A newspaper journalist arrives on the scene to get the scoop, and soon comes along when they leave - for Mongo again.
But Zarkov quickly discovers his error, and they head for Mars, presented in this film as a desert world with at least one advanced city. The first episode is clumsy in two ways. The main one is that it shows that the Queen of Mars is already working with Ming the Merciless, rather than having him appear later for shock value. At first appearance, he makes like he is serving her ends, rather than using her for his own. The second reason is that although the Martians wear unusual clothes, they are all in human form, except for the two she sends to Earth, who resemble the Clay People who appear later and who are not under her control. These two are teleported by a different beam, whereupon they immediately die, never having scared anyone on Earth nor ever being discovered by them.
The plot sequence is:
- Destroy the Nitron Lamp which is draining the Earth's atmosphere
- Restore the Clay People to their original human form
- Defeat Ming
This serial has fewer settings than the other two. Most of the action is the back and forth common in the cheaper serials of the era. Here it's between the Martian city and the land of the banished Clay People; there are also Forest People, mere primitives. The Queen of Mars has used her magic (she also teleports) to turn those subjects with whom she has been dissatisfied into clay in humanoid form, capable of melting into walls of clay and later re-emerging.
The civilization of the planet Mars has technical abilities of varying plausibility.
- With their winged helmets and long capes, and under the lower Martian gravity, its inhabitants, and also Flash and Zarkov, are shown able to glide.
- The Martians can make a "bridge of light" to cross a gap in their city walkways, but there is no lock and the guards do not stop anyone from turning the switch on from either end. Also, no one starts to cross the bridge only to have it turned off.
- The Clay People have a one-car subway that leads to the heart of the main city, with no explanation (it's not a high-volume commuter rail). This set was later used in the Buck Rogers serial, though increased in size.
The sequel to this serial, Flash Gordon Conquers the Universe, copies many of its plot points. Yet that serial has much more variety and action.
During the 1950s, the three serials were shown on television. To avoid confusion with a made-for-TV Flash Gordon series airing around the same time, they were retitled, becoming respectively Space Soldiers, Space Soldiers' Trip to Mars, and Space Soldiers Conquer the Universe.