Jim (Johnny Weissmuller) is assigned to accompany a government agent into the interior to get the native's approval for copper mining. Unknown to Jim, Arco (Robert C. Foulk), also wants approval but for oil, not copper. To obtain the land for themselves and eliminate the unwilling native chiefs they create a sham headhunter tribe. Arco and his henchies make a series of raids on the villages which he is able to blame on Jungle Jim.
Valley of headhunters is less fantastical than the other Jungle Jim's with an unscrupulous bad guy looking to rob natives of their mineral source - there's more of a story here than just throwing plenty of action in the mix. Ok it's not gritty, though there's some spears piercing and a tribal girl getting shot whilst she's in a box - you see the henchman who does this is really nasty. There's a certain repetition of the heroes getting captured, then escaping and then captured once again, but there's plenty of fisticuffs and spears flying to entertain.