The Rhedosaurus is a giant carnivorous man-eating dinosaur-like monster and the main antagonist of the 1953 film, The Beast From 20,000 Fathoms.
The Rhedosaurus in the film was one of the last surviving members of its species, awakened by a nuclear test in the Arctic. It made its way down the North American coast, destroying everything in its path and ending up in New York, its original home. Attempts to kill it were complicated by an ancient disease it carried; spilling its blood freed the plague, which was almost as deadly as the dangerous dinosaur itself. The Rhedosaurus was eventually killed at Coney Island when a radioactive isotope was shot into a wound on its neck, both fatally wounding it and also neutralizing the disease. The radiation also incinerated it, causing it to burn the island.
- The Rhedosaurus was one of the main inspirations for Godzilla, along with King Kong.
- The Rhedosaurus puppet was used again in the film, Planet of the Dinosaurs where it played a Rhedosaurus again that was doomed to be killed by the Tyrannosaurus Rex.
- The Rhedosaurus appeared in the 6th episode of the 2nd Season of ABC's Whose Line Is It Anyway?.