The Enid Blyton Adventure Series

Book 5: The Mountain of Adventure (Part 2) (1x14)

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Unaware of the children's plight, Bill proposes marriage to Allison and she accepts. But her happiness is clouded as the children fail to turn up when they should. A search is impossible until morning, the mist is too thick. While wandering in the foothills, the children see Alexai being pursued by dogs. Hans is rescued but is in a coma.