On December 31, 1999, a costumed man warns Peter about the dangers of Y2K. Peter locks his family up in a bomb shelter that evening. A nuclear holocaust occurs at the stroke of midnight, destroying much of Quahog and mutating or injuring many of the surviving citizens. The Griffins are free from mutations.
When food runs out, the family travels to Natick, Massachusetts, in hopes that the “Twinkie” factory survived. On the way, Stewie is exposed to nuclear waste and later mutates into an octopus-like creature. Upon their arrival at Natick, they establish a town, dubbed New Quahog, which Peter mismanages into chaos. Octopus Stewie notices that he has put on weight, and then begins to lay eggs.
Peter is eventually kicked out of the town he founded, and his family follows him, deciding where they should go next: a Carvel factory in Framingham, Massachusetts. Meanwhile, Stewie’s spawn hatch, and begin to kill the New Quahog citizens.
The episode ends in a live-action parody of a famous episode of Dallas, where Pam Ewing wakes to find her husband Bobby in the shower. She tells him about the episode, which was apparently a dream. This is a parody of the famous Dallas shower scene, where an entire previous season of Dallas was revealed as a dream.
- After the citizens of New Quahog kick the Griffins out and slam the city gates, Brian is absent for several scenes. Only after they start walking down the road in a line does he return.