Forbidden Worlds #9 (American Comics Group, September 1952) is a five-story pre-Code horror anthology behind a Ken Bald cover, and one of the leanest issues of the series' early run — the page count had just dropped to 36. The opener, "The Flying Head", is the issue's calling card: the severed head of an ancient wizard that retains its hideous power and, inconveniently for everyone nearby, levitates. "Doom of the Gnomes" takes an unexpectedly ecological turn, with children learning the secret of the gnomes and racing to save them from humanity's destructive nature — a striking premise for a 1952 dime horror comic. "The Phantom Fountain" sends a search for the Fountain of Youth badly wrong, unleashing murderous phantoms on the citizens of Florida. Rounding out the issue are "Out of the Night" and "Bride of the Swamp Monster", plus an editorial page, "From Your Editor — To You!". Interior art comes from Jon L. Blummer, Al Camy and Art Gates, under editor Richard E. Hughes.

Forbidden Worlds launched in July/August 1951 as a dime comic subtitled "Exploring the Supernatural!", the companion to ACG's Adventures into the Unknown — the medium's first ongoing horror title. ACG was a small, resolutely independent New York publisher founded by Benjamin W. Sangor and co-owned by Fred Iger, and its horror line kept a house style distinct from the competition: atmospheric, often wry, and far lighter on gore and sexual content than the EC and Harvey books of the same year. That restraint is one reason both ACG horror titles survived the 1954 Senate subcommittee hearings and the Comics Code without wholesale reinvention. Issue #9 catches the series mid-compression: monthly since #7, and squeezed from 52 pages at launch down to 36 here, with the editorial page doubling as reader-retention device. The series ran 145 issues to August 1967, was briefly rebranded Young Heroes in 1955, and won the 1964 Alley Award for Best Regularly Published Fantasy Comic.

Read today, issue #9 rewards attention for its odd tonal range. "The Flying Head" is pure grotesque; "The Phantom Fountain" is Americana horror, turning a school-textbook legend against the state it supposedly founded; and "Doom of the Gnomes" is something else entirely — a children-versus-adult-destructiveness fable that reads, seventy years later, like an accidental piece of proto-environmental fiction lodged in a monster magazine. The issue is also a clean example of ACG's working method: three journeyman artists, five stories, one dime, delivered monthly. And because the 1952 material is generally treated as public domain in the United States, this number is freely readable through Comic Book Plus and the Digital Comic Museum, and has even been reissued as a print-on-demand public-domain reprint.