Mark of the Gorilla is a 1950 film starring Johnny Weissmuller based on the comic strip Jungle Jim.
[3] Gorilla attacks on humans come as a surprise to Jungle Jim, since the creatures are not known to exist in this part of Africa.
On his way to see Frank Bentley, warden of the Nairobi animal preserve, Jim encounters a young woman in distress, Nyobi, and saves her life.
Bentley is ill, being treated by Dr. Brandt, who unknown to all is in league with fortune hunters trying to find a trove of Nazi hidden gold.
Barbara Bentley, the warden's niece, goes along with Jim and learns that men are wearing animal costumes, disguising themselves as gorillas and lions, to make deaths appear accidental.