Jenna makes a wish on her 13th birthday to be 30 and grown up. When she wakes up the next day she finds herself, miraculously, just weeks away from her 30th birthday. The new, older Jenna is a successful magazine editor with friends in high places and a lion's share of potential suitors. The problem is that her mind hasn't matured with her body and Jenna finds it a little more terrifying than cool to be living on her own.

Tribal nitwits, Zed and Oh, are two guys living in the year one. Neither one can hunt nor gather, so they are thrown out of their Neanderthal community and dung-and-stick huts. Zed eats the forbidden fruit and the two become curious about what may lay outside of their limited little world. They decide to embark on a journey through the ancient world. On their travels they meet Cain and Abel, Abraham and Isaac. They wind up in Sodom where their girlfriends...