In DINOSAUR ISLAND, a military deserter steals the identity of a dead man and becomes "John Lee." After years on the lam while acquiring skills as a yogi and a thug, John Lee sets sail on Captain Sykes' clipper ship to finally head back to England with his new identity. However, when Dr. Pikeham discovers that "John Lee" is an imposter, instead of turning him into the authorities, he offers him a job as his personal aide and protector on forays to dangerous, primitive islands so he can continue his work of studying and cataloguing the native animals. While on a shore expedition, John, Pikeham, and Sykes abandon Pikeham's scientific equipment and flee back to the ship before Siamese pirates can attack. Losing the pirates in a typhoon, the damaged ship encounters a mysterious island. When they go ashore to gather supplies and items to repair the ship, they encounter dinosaurs. And some of them are carnivorous...