A wolf mother has given birth, but the warm bundle snuffling next to her brings only anguish. The pup, otherwise healthy, has a twisted leg, and the mother knows what the harsh code of the pack demands. Her pup will be taken from her and abandoned on a desolate hill. The pack cannot have weakness - the wolf mother knows that her pup is condemned to die. But alone in the wilderness, the pup, Faolan, does not perish. This is his story - a story of survival, of courage, and of love and triumphant. This is Faolan's story, the wolf pup who rose up to change forevever the Wolves of the Beyond.
In the first chapter, which is more like a prologue, Morag, who is pregnant with Faolan and his siblings, is seen going by-lang, which literally means in the wolf language 'deeply away'. She finds a fox den, chases away the fox and settles down. Later, it is shown that Shibaan, the Obea of the MacDuncan clan, is actually following her.
Morag has three pups, but one of them, the only silver pup in the litter, is a malcadh, a cursed wolf. Shibaan, the Obea of the MacDuncan clan, finds Morag and takes the silver pup away.
She abandons the pup on a piece of ice on the river that is about to crack. She is said to have no feeling for the pups she abandons and she 'might as well be carrying a clod of dirt'. The ice cracks, and the malcadh is thrown in the raging river.
The point of view switches to a female grizzly, who is standing by the river moaning. Apparently, her only cub was taken by cougars, and she intended to commit suicide. After a while, the pup is snagged in her paw. When she sees him, she sees the pup as her 'gift from the river', so she named him Faolan; Fao means river and wolf, and Lan means gift. (In actual fact, Faolan is an Irish name which means 'wolf'). She takes him back to her den and nurses him. Faolan eventually learns to call her Thunderheart, for her large thunder-like heart.
The next few chapters describe their life together, and show how Thunderheart eventually has to enter the 'Cold Sleep', or hibernation. She picks a connection of tunnels under what is assumed to be a volcano, and goes to sleep, but allows Faolan to run out and catch prey.
One day when Faolan is out, Thunderheart wakes up. Confused by sleepiness, she thinks that Faolan is gone and charges out, forgetting that she had given him permission to go out. When Faolan returns and finds Thunderheart missing, he starts to get anxious too.