Whilst building a harbour on a Caribbean island, construction workers discover two perfectly preserved dinosaurs—a brontosaurus and a T-Rex—frozen under the sea for millions of years. After being brought ashore, the prehistoric creatures thaw out and are struck by lightning during a storm, bringing them back to life. As the beasts wander the island, looking for food, construction boss Bart Thompson (Ward Ramsey) tries to ensure the safety of the islanders. Meanwhile, a neanderthal (Gregg Martell), who has also emerged from the ocean, befriends local boy Julio (Alan Roberts) and protects him from his wicked guardian Hacker (Fred Engelberg).
Dinosaurus! is the one in which the 'cute' kid (ie., thoroughly irritating brat) and the caveman ride on the back of the brontosaurus, putting the audience squarely in family territory—good clean fun with very little to seriously scare the young 'uns. The juvenile nature of the film, along with some naff neanderthal-based comedy, make it just a little too cloying at times, but as a fan of dinosaur movies in general, and especially those that make use of stop motion animation, I couldn't help but be entertained. Yes, the animation is a long way from Harryhausen standard, and there's some even worse puppetry, but it still proves to be a reasonably decent dose of mindless fun. Of course, it doesn't hurt that the film also features two helpings of eye candy—tasty blonde Betty (Kristina Hanson) and dusky island beauty Chica (Lucita Blain)—to hold one's attention whenever the dinos are off-screen.