The world is nearing the 22nd century, and it's on the verge of environmental destruction. Humanity's only hope is to travel back in time 85 million years to start over. We meet the Shannons, who are attempting to survive in this world. After illegally having a third child, Jim Shannon is arrested for hitting a police officer who finds the third child in his home.
After serving two years of his sentence, his wife Elizabeth tells him she has been recruited to Terra Nova, the new civilization 85 years in the past. She helps him escape his prison and tells him to meet her at the portal. Jim rescues their third child, Zoey, and meets his family in time to go with them to Terra Nova.
Once there, the family sets up shop in the cleaner world, and prepares for their new life on Terra Nova.