Riders of the Whistling Skull

When young Betty Marsh (Mary Russell) learns that her archaeologist father is missing, she calls upon cowboy heroes the Three Mesquiteers -- Stony Brooke (Bob Livingston), Tucson Smith (Ray Corrigan) and Lullaby Joslin (Max Terhune) -- to rescue the man. This leads the trio to a treasure map and, ultimately, to a treacherous place called the Whistling Skull: a rock formation occupied by a Native American cult, mummies and a madman who has been pulling the strings all along.