 When one of the scientists disappears from Yells Back Butte, where a Navajo Tribal Police officer was killed, will Leaphorn and his young colleague Jim Chee put their faith in skinwalkers, medieval plague -- or something more human and more sinister?People's conflicting beliefs are never easily resolved, as Acting Lieutenant Chee, a traditional Navajo who is studying to be a shaman, learns to his sorrow once again.We readers are luckier.