Challengers of the Unknown

DEEP IN THE SOUTH AMERICAN JUNGLE, A REAL AND SINISTER MENACE LURKS IN THE SHADOWS OF THE SUPERNATURAL... In a remote lake, a legendary monster, incredibly vicious, surfaces after a sleep of centuries. Acting to protect its oil stake, the U. S. Government calls in... The Challengers! Men wtih young faces and old memories move mysteriously in the area, speak in low tones in the capital city. The country's president alerts... The Challengers! A dying man names a desert fort, many miles away... Bisarre mechanisms keep the curious away.. Unseen enemies... Strange accidents... Strong-arm assailants... A hair-raising test fo the celebrated ingenuity of the CHALLENGERS OF THE UNKNOWN