 Produced as a TV series pilot, this film was determined to be too violent for  the small screen and given theatrical distribution instead. Added for this  release was an exploitation device called the "Fear Flasher/Horror Horn",  ostensibly to warn the audience of the "Four Supreme Fright Points" (although  it was not applied to the pictures most explicitly violent moment, the  climactic fate of the villain). This device was explained in an introductory  sequence narrated by _William Conrad (I)_(qv). Upon first showing on US  network television, both the device and its explanation were deleted, but in  subsequent syndication to local stations in the 1970s and 80s, some such  prints were seen.