A pack of wolves makes a sudden savage return to the Rocky Mountain ranching town of Hope, Montana, where a century earlier they were slaughtered by the thousands. Now shielded by law as an endangered species, they reawaken an ancient hatred that will tear a family, and ultimately the town, apart.

At the centre of the storm is Helen Ross, a 29-year-old wolf biologist sent alone into this remote and hostile place to protect the wolves from those who seek to destroy them. The Loop charts her struggle, and her dangerous love affair with the son of her most powerful opponent, the brutal and charismatic rancher Buck Calder.