It s fall in the Sierra Mountains， and Anna Pigeon is slinging hash in Yosemite National Park s historic Ahwahnee Hotel. Four young people， all seasonal park employees， have disappeared， and two weeks of work by crack search-and-rescue teams have failed to turn up a single clue; investigators are unsure as to whether the four went AWOL for reasons of their own-or died in the park. Needing an out-of-park ranger to work undercover， Anna is detailed to dining-room duty; but after a week of waiting tables， she knows the missing employees are only the first indications of a sickness threatening the park. Her twenty-something roommates give up their party-girl ways and panic; her new restaurant colleagues regard her with suspicion and fear. But when Anna s life is threatened and her temporary supervisor turns a deaf ear， she follows the scent of evil， taking a solo hike up a snowy trial to the high country， seeking answers. What waits for her is a nightmare of death and greed-and perhaps her final adventure.