Legend of Dinosaurs & Monster Birds is a Japanese giant monster, or kaiju, film from 1977. Drastic changes in the weather surrounding a village along the rim of Lake Sai causes a plesiosaur to awaken from the deep. Elsewhere, a cavern within Mt. Fuji serves as the nest of a gigantic egg that begins to move and crack as the area thaws out, eventually resulting in the emergence of a pterodactyl. As the flying dinosaur flees from its mountain home, it seems to make a beeline for Lake Sai, where a skirmish between the monsters occurs with much collateral damage.