The anthology, in addition to running original stories, also included writer Roy Thomas and penciler Don Heck's loose adaptation of Edgar Allan Poe's "The Masque of the Red Death" in issue #2 (Dec. 1969). Writer Denny O'Neil and Tom Palmer adapted the Poe story "The Tell-Tale Heart" in issue #3 (Feb. 1970). Thomas and EC Comics veteran Johnny Craig adapted H. P. Lovecraft's "The Music of Erich Zann" as "The Music From Beyond" in #5 (June 1970).
Industry legend Jack Kirby, in a rare instance of scripting for Marvel before leaving for rival DC Comics for a time in 1970, wrote and penciled "The Monster" in #4 (April 1970), and "And Fear Shall Follow" in #5 (June 1970), both inked by John Verpoorten. Kirby, inked by fellow Golden Age great Bill Everett, also drew the latter issue's cover. Everett himself wrote and inked (with penciler Dan Adkins) the story "Believe It...Or Not" in #8 (Dec. 1970).
Designed to compete with DC Comics' successful horror titles such as House of Mystery and House of Secrets, the book, like its companion comic Tower of Shadows, sold poorly despite such notable talent. After its first few issues, the title began including reprints of pre-superhero Marvel monster stories and other SF/fantasy tales from Marvel's 1950's and early 60's predecessor, Atlas Comics. After the eighth issue, the title changed to Monsters on the Prowl, and the comic became almost exclusively a reprint book.