Edgar Rice Burroughs 
Tarzan and the Leopard Men 

An amnesiac Tarzan and his monkey companion Nkima are taken by an African warrior to be his guardian spirits, and as such come into conflict with the murderous secret society of the Leopard Men, led by Gato Mgungu. From America, a young woman arrives in the territory in search of a loved one presumed missing, and two young men (also from that country) come in search of ivory.