FINDING THEIR MISSING GRANDMA WILL BE NO SMALL FEAT! Rubi and her much more daring--and skateboard-obsessed--brother, Quinn, are visiting their grandmother on beautiful Vashon Island for the weekend. It's the first time they've taken the ferry from Seattle by themselves. But weirdly, when they arrive, Nana is nowhere to be found! Then their Uncle James lets them in on a little secret: Bigfoot may have been spotted! And their Nana isn't any old grandma--she's the most famous Bigfoot hunter around! Trouble is, Nana should've returned by now. And nobody in all of Puget Sound has seen her! At least... nobody human. Rubi and Quinn will have to follow the footprints (and scat!), crack the clues, and rely on each other to find their Nana and bring her home... that is, unless Bigfoot finds them first !