Bradley, Brian, Nate, and Lucy visit a haunted hotel on Halloween, but once inside they realize that they have seen plenty of people going in but none coming back out.
In an overpopulated world where all signs of nature have been obliterated and a wall has been erected to keep out plague-ridden animals, twelve-year-old Mika refuses to believe that his twin sister was killed after being abducted, and continues to search for her in spite of the dangers he faces in doing so.
