Rich and his hounds track Rich's nemesis, the killer mountain lion Three-Toes, across the length of Montana's Ruby Valley. In Alaska, a young prot g brings Marty the new snowmobile engine he's been waiting for. Eustace races the winter frost to seed his field in North Carolina and in Northwest Montana, Tom receives a commission from a neighbor to build a primitive bow, with a deadline that puts his endurance to the test.

Marty rushes to make the most of an extra pair of hands. Tom's grandson comes for a visit but soon learns that there's no such thing as vacation in the Yaak. Charlie heads out on a hunt for shed moose antlers. And in Montana's Ruby Valley, Rich Lewis' dogs are hot on the scent of a mountain lion when their hunt takes a dangerous turn.