Palmer's goal for "Fantastic Adventures" was to create a magazine that published fantasy fiction but was the literary equal of the quality magazines—the "slicks", such as "The Saturday Evening Post". Although mixing science fiction with fantasy was not popular with sf fans of the era, Palmer consciously promoted the magazine as containing the best of both worlds; the slogan on the cover read "The Best in Science Fiction", but Palmer also wrote blurbs in "Amazing Stories" for "Fantastic Adventures" in which he extolled the value to a reader of getting both genres in a single magazine. "Fantastic Adventures" competition included "Unknown", which had been launched just a couple of months earlier, in March 1939, and "Weird Tales", which was first published in 1923; but instead of attempting to emulate either one, "Fantastic Adventures" focused on adventure stories in the style of Edgar Rice Burroughs. Palmer probably acquired some fantasy-oriented material that had been submitted to "Amazing Stories", which gave him an immediate stream of submissions to work with. However, according to Ashley the first issue was quite weak: The cover story was "The Invisible Robinhood" by Eando Binder, and other contributors included Harl Vincent, Ross Rocklynne and A. Hyatt Verrill. Features included a quiz, an author profile, and a comic strip, titled "Ray Holmes, Scientific Detective"; the reader was supposed to solve the mystery based on the clues given in the strip. It was a failure and disappeared after the first issue. The back cover, "The Man from Mars", by Frank R. Paul, was more successful, and illustrated back covers became a regular feature of the magazine.