I'm rather fond of Johnny Sheffield in these "Bomba meets..." films. Apart from reminding me of "Kurt" from "the Sound of Music" (1965) he remains quite a fun paragon of decency and simplicity in a jungle environment soon to be compromised/exploited/destroyed by anyone who comes along thinking they know best... In this little yarn, our hero gets caught up with some nasty diamond smugglers who are posing as scientists whilst killing and enslaving the natives as they search for the "Mountain of Diamonds". Of course it's filmed in California, and the animal scenes look very much like stock-shots; ...