* "Dark Interval" (1946)
* "Blood Tide" (1950)
* "The Witch" (1952)
* "The House of Shadows" (1953)
* "The Haunted Room" (1954)
* "The Devil's Spawn" (1955)
* "Shadows of Evil" (1956)
* "The Curse of Salem" (1957)
* "The Horror from the Depths" (1958)
* "The Night of the Screaming Skulls" (1959)
* "The Ghoul" (1960)
* "The Werewolf of Paris" (1961)
* "The Vampire of Venice" (1962)
* "The Mummy of Thebes" (1963)
* "The Phantom of the Opera" (1964)
* "The Man Who Could See Tomorrow" (1965)
* "The Invisible Avenger" (1966)
* "The Secret of the Black Tower" (1967)
* "The Treasure of the Golden Dragon" (1968)
* "The Island of the Lost Souls" (1969)
* "The Valley of the Damned" (1970)
Non-Fiction:
* "The Real Sherlock Holmes" (1957)
* "The World's Most Mysterious Murders" (1959)
* "The Strange Story of Jack the Ripper" (1961)
* "The Bermuda Triangle Mystery" (1964)
* "The Loch Ness Monster: Fact or Fiction?" (1966)
* "The Yeti: The Abominable Snowman" (1968)
* "The World of the Supernatural" (1970)