Alone in the Canadian wilderness in the 1620s, after her father's death, Ruth has to learn how to survive. During the first winter, she befriends a wolf and gives him the name of Zak. She soon has a pack of wolves and learns to hunt with them. Contact with the local Indians brings with it communication problems. Because she has a pack of wolves, the Indians give her the name Jaga na Kala-Mother of Wolves. When trappers murder one of the Indians, she has to determine which of three trappers caused the death of one of the Indians.