Former high school friends run into each other years later and drunkenly decide to make good on their promise to marry each other if they're both still single by 30 - only to discover too late all the things they liked about each other when they were younger have changed.
Faced with impending doom from a planet-killing asteroid, a couple flee to the hills of Tennessee to spend their last days together - but the chaotic breakdown of society disrupts their peaceful plans.
