1940 - 1942
Flash Gordon Conquers the Universe was one of the few bright spots for sci-fi in 1940. This serial was based on Alex Raymond's Flash Gordon comic strip continuity involving Prince Barin and his kingdom of Arboria.
Other sci-fi films of 1940 include The Green Hornet serials and the Mysterious Doctor Satan serials. The Doctor Satan serial was intended to feature Superman as the main hero, until right of use became an obstacle. So the writers created a character of their own creation, called The Copperhead.
Adventures of Captain Marvel is a twelve-chapter film serial directed by John English and William Witney for Republic Pictures, adapted from the popular Captain Marvel comic book character then appearing in Fawcett Comics publications such as Whiz Comics and Captain Marvel Adventures. It starred Tom Tyler in the title role of Captain Marvel and Frank Coghlan, Jr. as his alter ego, Billy Batson.
This serial was the twenty-first of the sixty-six serials produced by Republic and their first comic book adaptation, not counting comic strips. The serial featured an adaptation of the Fawcett Comics superhero, placed within an original story. He fights a masked criminal mastermind called The Scorpion who is determined to gain control of a powerful weapon disguised as a scorpion figurine.
Harmon and Glut claim that Adventures of Captain Marvel is "unquestionably one of the finest movie serials ever made, possible the best with the exception of the three Flash Gordon epics." Cline describes this as one of the most outstanding of all serials and Republic's "masterpiece." He writes that Tyler's "striking performance...remains in thousands of minds as the most memorable serial hero of all time - bar none."
The flying effects were performed with a dummy. The dummy was slightly larger than life, at 7 feet tall, and made of paper mâché so that it weighed only 15 lbs. The uniform was made of thin silk and a cotton jersey. Four pulleys connected to each shoulder and calf, which were strung on two wires so the dummy moved along them by its own weight.
In 1941, Man-Made Monster launched Lon Chaney Jr.'s career as a star in horror films and the film's success directly led to his casting in the big budget role of his career, The Wolf Man. The film was intended to be another vehicle with Bela Lugosi as the mad doctor, but was shelved and not released until 1941. Budgeted at a mere $86,000 on a 3-week shooting schedule. It was the cheapest feature film produced by Universal in 1941.
Other than The Ghost of Frankenstein, 1942 was completely void of any sci-fi worth mentioning. The Superman animation serials however hit a box office stride and built a fan following where the cartoon hero battled dinosaurs, confronted deadly meteors, and faced diabolical contraptions such as rocket cars and earthquake machines.
1943 to 1946
While The Crimson Ghost was really a series of matinee serials, it was the best sci-fi this period had to offer in terms of box office features. The Crimson Ghost was directed by Fred C. Brannon and William Witney with Charles Quigley and Linda Stirling playing the leads.
This was Witney's last serial, after a career that left him one of the most praised of all serial directors. The serial was re-released as a six-episode television series in the 1950s and as a television film called Cyclotrode "X" in 1966. In the 1990s the serial was one of only two Republic serials to be colorised.
The villain of the serial, the Crimson Ghost of the title, is one of the most visually striking of the medium. The Crimson Ghost was budgeted at $137,912, although the final negative cost was $161,174 (a $23,262, or 16.9%, overspend). It was the most expensive Republic serial of 1946.
In order to prevent the audience deducing the identity of the Crimson Ghost, the studio cast stunt-man Bud Geary to embody the villain while several actors supplied the voice, including I. Stanford Jolley. Jolley's role was minor but he received fourth-billing and was therefore highly suspect.
When the Crimson Ghost was unmasked in the 12th and final chapter, he proved to be yet another actor entirely, Joseph Forte, who had played a character seemingly above suspicion at that point in the serial. Television's future Lone Ranger, Clayton Moore, played a rare villainous role in this serial as one of the Crimson Ghost's henchmen, a cold-hearted gangster named Ashe.
Other sci-fi films of this period worth a mention (more or less) include the Batman serial (1943) and Frankenstein Meets the Wolfman (1943). I mention the latter only for historic reasons, otherwise this studio chopped production is often lambasted by critics and viewers, though the film was actually a box office success.
The Frankenstein franchise continued to spiral with House of Frankenstein (1944). Originally Kharis the mummy, another Universal "classic monster", was to be in the movie but was removed because of budget restrictions. Glenn Strange was the fourth actor to play the Monster in Universal's Frankenstein series.
The actor who played the original Monster, Boris Karloff, was also present in the film, playing the role of Dr. Niemann. The only sci-fi offered in 1945 somewhat worth a mention is the serial The Purple Monster Strikes and perhaps Charlie Chan's The Jade Mask.
1947 - 1949
Another series of matinee serials, Superman was a "tremendous financial success" and played in "first-run theatres that had never before booked a serial." The serial was a popular success that made Kirk Alyn famous and launched Noel Neill's career. A sequel serial, Atom Man vs. Superman, also directed by Bennet, was released in 1950.
Superman's flight sequences were animated instead of live-action or model work. Harmon and Glut consider this to be the "weakest point of the serial", explaining that the "effects created by Republic for Captain Marvel were very convincing; even the more routine ones for the Superman TV series, always showing the same pose, were better."
While there were other effective special effects, in their opinion, they were undermined by the poorness of the flying sequences. The film crew did test an alternate method of filming the flying sequences: Kirk Alyn spent an entire day painfully suspended by visible wires in front of a rear projection of moving clouds.
Displeased with the results, Katzman fired the entire flight sequence production staff and used the animated method instead. A peculiar characteristic of the mix of animated and live-action footage is that Superman's take-offs are almost always visible in the foreground, while his landings almost always occur behind objects, such as parked cars, rocks, and buildings.
Other sci-fi films of this period worth a mention (being generous here) is Vesna (1947) and the serial Brick Bradford (1947), an adventurer travels to the moon to stop a madman from getting hold of the Interceptor Ray, a weapon that could destroy Earth.
It could be described as a pleasant surprise that Bud Abbott Lou Costello Meet Frankenstein (1948) warrants a worthy mention. This sci-fi comedy horror is full of scares and laughs. In 2000, recognized by the American Film Institute's 100 Years... 100 Laughs at #56. In September 2007, Readers Digest selected the film as one of the top 100 funniest films of all time.
Sci-fi films of 1949 include the serial King of the Rocket Men and It Happens Every Spring - which is more comedy than sci-fi. In King of the Rocket Men, Jeff King's atomic powered rocket suit was so advanced that it required only three operational controls: on/off, up/down and slow/fast.