Proposes a minute-by-minute chronology of the Chicxulub impact and its effect on the dinosaurs and other animals around the world. The "Last Day of the Dinosaurs" is a documentary about the extinction of the greatest animal species that ever lived. It portrays an asteroid hitting the Yucatan Peninsula as the cause of their demise.
In the Pacific Northwest of North America, a Quetzalcoatlus is flying above the landscape, looking for food. It finds a nest of Tyrannosaurus babies that have just hatched. It picks them up in its beak and starts eating them. Suddenly, the father appears and starts fighting the Quetzalcoatlus. He grabs it by the foot, but it manages to escape. As the father T. rex attends the nest, he finds only one of his babys has survived.
Meanwhile, an asteroid is speeding toward Earth. The narrator says that it was caused by the collision of two asteroids 165 million years ago, causing two multi-mile-wide asteroids to collide at over 1,000 miles an hour, sending fragments to be hurled in every direction. One of the fragments is heading towards Earth, but this "fragment" is over 6 miles wide.
In the Pacific Northwest, two male Triceratops fight for mating rights. One of them wins and the loser walks away. Suddenly, two T. rex attack and kill the Triceratops that lost. They start feeding on its carcass.
In what is today central Mexico, an enormous herd of Alamosaurus is roaming the plains in search of food. They are giants, even by dinosaur standards. They are 60 feet long and 40 feet tall, and they weigh 30 tons. Their huge size demands that they eat a lot of vegetation to maintain their bulk. Meanwhile, the asteroid enters the Earth's atmosphere. It is burning brighter than a million suns. The scorching light sears the Alamosaurus' eyeballs, blinding them, but they don't have to see it to know the asteroid is hurtling towards Earth. They can hear the ear-shattering explosion as it lands.
Then the asteroid hits the Earth in the Gulf of Mexico, near the Yucatan Peninsula. In a fraction of a second, it disintegrates into the planet. The air temperature near the crash site now reaches 600 degrees Fahrenheit. Most of the Alamosaurus are burned alive. Much of them were protected by the shadow of a large mountain, but are later bombarded by debris, struck by an 11.5 magnitude earthquake, and finally the species is almost completely wiped out by the blast pulse wave. In the Pacific Northwest, in a large valley, a pair of Quetzalcoatlus can see the impact, and as the asteroid strikes at a 30-degree angle, pieces rocket through the sky and in British Columbia, animals are frightened to see these huge trails of smoke and fire light up the sky. Then the 11.5 magnitude hits British Columbia, driving animals to flee from the valley.