The opening of "The Jungle" promises us a safari adventure with a science fiction element, but mostly what we get is a travelogue with lots of stock footage and padding (and the odd leopard attack). The movie is leisurely when you want it to be gripping, and tries to inject interest into the proceedings with badly staged matches between various wild animals (I had no idea that lions and wild boars were natural enemies in the wild, did you? I thought the big cats stuck to hunting herbivores, but apparently the producers knew better).
As for the actors: Cesar does his usual great job of rocking the mustache, and Marie Windsor is reasonably believable as the progressively thinking rajah's daughter (nice eyebrows, btw!). However, Rod Cameron is barely watchable as the hunter returning as the sole survivor of his expedition. I'm sure he was in demand in his day, but here he comes off as a Rent-A-Center Bogart : rough looking, but with none of Bogey's range or timing. He spends the movie going back and forth from stoic anger to angry stoicism, and any time the screenplay attempts to crank up some romantic sparks between himself and Windsor, you just have to laugh. That crabbed, knobby face isn't a good vehicle for tenderness.
The screenplay is not entirely without merit, although it does make some odd choices. Early in the first act, the screenplay makes a point of spending several moments where the heroes decide to bring along the obligatory clever young boy and monkey mascot, but then basically ignore them until ***SPOILER*** the monkey somehow gets hold of a live hand grenade during the mammoth scene and accidentally tosses near Windsor. This is so Cameron can prove his bravery by diving on it and saving her life at the cost of his own.***END SPOILER. It's possible that the Indian version of this movie (which I understand ran better than 2 1/2 hours), might have given the kid and the monkey more to do.
Another thing that makes the film show its age **SPOILER**is the issue of the woolly mammoths (the plot device that sets the safari into motion in the first place). When they finally appear, the way the scene is filmed, it's obvious that the "mammoths" (obviously elephants draped in shag carpeting) aren't really "attacking" anyone, or even moving all that fast, and yet Cameron immediately sets to trying to wipe them out with hand grenades. These days, the idea of destroying the last known specimens of a species thought to be extinct would be unthinkable, especially when all they seem to do is roll through the jungle at a nice walking pace.***END OF SPOILER***
So IMO, four stars, which is pretty good for a Robert Lippert production (normally Lippert hack jobs rate two or three stars at best). It's not a train wreck of a film, or anything; plus, it seems to mean well,with the rajah's daughter arguing for amelioration of the most repressive aspect of the "traditional ways" and the elements of "mixed race" romance that was pretty progressive in 1952. And there's some nice scenery and exotic spectacle. See it if someone offers to show it to you for free, but don't expect much except an interesting historical chapter of early fantasy cinema.