In year 2050, the humans becomes the hunted. The extinct animals comes back to life and take over the world. They are now the predator and humans are their prey. Gary Salazar, in his early thirties, did not survive in the invasion of the animals. But after he died, he wakes up in a body of an 18 year old teenager. The year is 2020, 30 years before the calamity that will change the world. He will try to prevent it from happening once again.