When it's known that 'Parents Day' is approaching at Faber, Hoover and the rest of the Deltas decide to somehow trick the rival Omegas into leaving town (and away from campus) so they can switch the Greek letters on their house and the Omega's house so the Deltas' moms and dads will be visiting them in the clean Omega house, while the Omegas' moms and dads end up in the messy Delta house.

A speech by President John F. Kennedy about the fear of nuclear war leads to Greg Marmalard and the rest of the Omegas building an elite bunker for survival with campus security funds, while Flounder ponders the meaning of existence. When a faulty test alarm sounds like a real warning of missiles launching, everyone goes into action... with the Delta's throwing a 'Welcome Russians' party to end all parties, while the Omegas just prepare for the end.

Dean Wormer gives the Delta House one week to clean up the house or face expulsion because of a new college bi-law of displaying clean frat houses. So, Hoover and the guys hire a house mother to help get things together. Meanwhile, Blotto enters a weightlifting contest to try to win the money that is required to make repairs to the house.