You're ready to relax in the tropical island paradise of Tahiti-and next minute, you're helping madcap scientists solve a prehistoric mystery: Who were the first people of the Pacific? And where did they come from?

To find out, you've got a crazy-sounding choice: Go west to catch rats (rats??!!) or east to build a raft (a raft??!!). But it's all real science-and it's all real adventure. So, are you ready? Which path will you pick ... By Rat or By Raft?