I remember seeing this movie on TV when I was like 7, where a group of pioneers found this island ruled by chimps who captured some of the pioneers and sacrificed them by putting them on an altar thingy and smashing a rock on their face. I remember the remaining pioneers befriending some of the chimps, because some of 'em were good. Or were they bad? And there was one bit where they were hiding in a bush from a raid of chimps, and there were chimps hiding in the bush with them, and they helped camoflauge them.