News comes to a small village in the French Alps that an enormous white dog is running wild in the mountains. Sebastian is determined that it shall come to no harm.
César takes Sebastian higher up the mountain pass than he has ever been before, and shows him the way to the Italian frontier.
Because they don't understand Belle, the villagers are terrified of her, and determined to hunt her down. But Sebastian intervenes.
A sinister newcomer to the village gets work locally, and insinuates himself into Cesar's household.
Sebastian is suspicious of Norbert, especially when he sees him meeting a strange car.
Much to the disquiet of Angelina and her grandfather, Norbert begins to exercise a bad influence over Jean.
Jean tricks Sebastian and takes Belle for training up to the Grand Baou in accordance with Norbert's instructions.
The two customs men become suspicious about Belle's activity.
Angelina's plans for a happy Christmas appear to be ruined, and Sebastian goes up into the mountains in search of Belle.
The Commissioner from Paris arrives in the village just as disaster hits the chalet.
Norbert takes to flight, and Jean Is involved in the Commissioner's investigations.
Has Sebastian escaped the avalanche? And where is Belle?
Jean tries to find the evidence which will prove his innocence.
