Extensive stock footage from 1949's Lust for Gold is used to flesh out the Columbia potboiler Secret of Treasure Mountain. The producers went so far as to hire one of the actors of the earlier film, William Prince, in order to match the old footage with the new. The plot is set in motion some 200 years ago, when a Spanish soldier buries a fortune in gold somewhere in Apache country. Angered at this invasion of their sacred land, the Indians place a curse upon the gold -- and, by extension, upon all those who will come into contact with the precious mineral in the future. The story proper begins in The Present, as a group of adventurers, many of them on the shady side (none shadier than villain Raymond Burr), embark upon a search for the gold. Sure enough, these modern-day prospectors fall victim to the curse one by one, usually as a result of their own greed or lust -- yes, lust, since shapely Valerie French and Susan Cummings are among the gold-seekers.