The friends and family of American tycoon Thorton Armitage are enjoying a luxury cruise about the yacht The Titan. Steve, the personal tutor and mentor of Thorton Armitage's son Billy, teaches Billy about the theory of evolution. Billy's older sister Elaine flirts with Steve, who mistakenly believes that she is in love with him. Elaine's fiancee watches from a distance as the two kiss. When Steve looks to confess his love for Elaine, she explains that the kiss meant nothing. Embarrassed and enraged, Steve threatens to quit the crew.
A tempest forms, threatening to destroy the ship. Luckily, a Chilean submarine surfaces and encourage the crew of the Titan to board. The yacht is destroyed just as the submarine dives. The submarines' crew see strange underwater creatures, then surface on a tropical island. The crew soon discover that dinosaurs exist on the island and promptly escape from a stampede. Later, the Chilean Navy are attacked by a prehistoric rhinoceros-like mammal known as an Arsinotherium. The arsinotherium gores many of the sailors to death, before knocking the fleeing sailors from a log bridge.
The survivors, assuming that they will never see civilization again, build a shelter with which to live in. After Ned Hallet shoots a Brontosaurus (now Apatosaurus), the sauropod retaliates by destroying the shelter. Ned Hallet leaves the camp in anger after being scolded and takes his frustration out on a baby Triceratops. The mother rushes to the aid of the infant and kills Hallet.
While the camp are exploring ancient ruins, a block gives way, causing Elaine to fall. Elaine is attacked by a Pteranodon which is driven off by Steve. Shortly afterwards, the crew are chased into a temple by an aggressive Stegosaurus. The crew is trapped between the Stegosaurus and a Tyrannosaurus. Rather than kill the crew, the two dinosaurs fight one another. In the end, the Tyrannosaurus kills the Stegosaurus and feeds it to its infant as the crew escapes.
After searching the temple, the crew discover a metal needed in order to get their radio to work. The crew try to send out an S.O.S., but the volcano begins to erupt, causing mass hysteria among the dinosaurs. A Pteranodon destroys the tower used to conduct the signal, leaving the crew stranded to be killed by the volcano. Facing death, Elaine and Steve finally confess their love for one another. As Billy faints from heat exhaustion, a rescue team of air planes arrive and save the crew from certain doom.
Aboard a rescue ship, Thorton Armitage boasts of his adventures. He is mocked, when suddenly a Pteranodon flies aboard the ship, proving his story to be true. The film ends with Steve and Elaine sharing a laugh as they look forward to their new life together.
In the 2-disk 2005 DVD release of King Kong, the surviving footage from Creation is shown. Also, a dramatization of how the entire film might have been if completed is also presented, using a combination of the existing footage, along with production sketches, test stills, and a voiceover narrator. From this dramatization, it appears that much of the plot was taken from the Edgar Rice Burroughs story The Land That Time Forgot.
In the remaining footage, two infant Triceratops play tug of war with a vine before their mother separates the two. The loser of the conflict wanders off into the jungle where it views a chimpanzee, a jaguar, and eventually an armed sailor identified by the script as Ned Hallet. Hallet stumbles upon the infant Triceratops and shoots it through the eye. The dying infant screams out to its mother who charges to the rescue, chasing Hallet through the jungle. The final scene in which Ned Hallet is gored to death by the vengeful mother is lost. Merian C. Cooper intended to use the footage in King Kong, but felt that it didn't fit in with the rest. An altered Triceratops scene does appear in the 1932 Kong screenplay and the film-novelization.
Parts of the remaining footage can also be seen in the computer game "Dinosaur Museum" by Perspective Visuals and the educational video "More Dinosaurs".