In 1924, the one-year-old Weird Tales magazine had not yet achieved the fame (or notoriety) that would make it a best-seller synonymous with fantasy and horror stories...
...so, for a couple of issues, the publisher brought in the famed Harry Houdini to write the cover-feature.
Sales didn't pick up, and the magazine was forced to go from monthly to quarterly.
For the third and final Houdini cover story...
...the publisher had an up-and-coming young author ghost-write the final Houdini entry, doing a first-person mystery-adventure instead of the non-fiction charlatan spiritualist exposes of the previous issues.
The writer was H P Lovecraft.
You can read both the tale and the story behind it (explained in a letter by Lovecraft to fellow author Frank Belknap Long HERE.
It's been reprinted numerous times, ususally under the title "Under the Pyramids", and credited to Lovecraft.
Weird Tales and Lovecraft remained together, each inspiring the other to amazing creative heights.
Lovecraft began work with Houdini and C M Eddy, Jr. on a non-fiction book entitled "Cancer of Superstition", but Houdini's death ended the project which was fully-outlined with several chapters written.