When six friends are hiking in the mountains near Portland, it's another typical Saturday. Then impetuous Amy chases a mysterious shape through the trees, starting something that will change their lives forever. The chase ends with a dying scream and a strange discovery. The six of them continue their day: four to a weekly tryst, the others to a weekly game night. Then everything changes. Inexplicable events begin to occur, from physical reactions they can't control to legendary visitors they can't believe they're seeing. Does Bigfoot really exist? The only way the answer will be found is to return to the mountain where it all started-if they can survive that long.