Comic Title: House of Secrets #23
Publisher: DC (National Comics Publications, Inc.)
Address: 575 Lexington Avenue, New York, NY
Cover Date: August 1959
On Sale Date: June 18, 1959 Copyright Date June 18, 1959
Source: Library of Congress, Periodicals 1959

Frequency: Monthly
Cover Price: $0.10
Page Count: 32
Editor: Jack Schiff

Title: "I Scout Earth's Strangest Secrets"
Pages: 8

Feature(s):
Mark Merlin (of Earth-1)

Writer: Bob Haney
Artist: Mort Meskin

Reprinted In:
Phantom Stranger #15 (1971)

Feature Character(s)

• Mark Merlin (first appearance; last appearance in House of Secrets #58; next appearance in House of Secrets #24)

Supporting Character(s)

• Elsa Magusson (first appearance; last appearance in House of Secrets #58; next appearance in House of Secrets #24)

Villain(s)

• A race of amoeba creatures and a museum manager (no further appearances)

Other Character(s)

• Mrs. Phipps, Mr. Wakely, Mr. Cole, and Mr. Lemmon (Mark Merlin's clients; no further appearances)

Synopsis:
Mark Merlin, private investigator of the supernatural, takes on several cases that appear to have unnatural explanations. Some of the cases have natural explanation, such as mountainside creatures that are really just large shadows. On another case Mark is able to expose a deliberate hoax. Mark proves that a museum, which is believed to be haunted, has actually been the victim of a hoax using magnets to move metal objects invisibly.

Merlin also has a "Question Mark File" containing cases he can not explain or classify. On one such case a strange creature is found in an unmapped cave. When Mark investigates he fall through a seam in the rock and discovers an enitre species of giant single-celled creatures. The creatures attack him, but he seals off the seam, trapping them inside.