When the Birds Fly South

Dan Prescott, an American adventurer, discovers the hidden valley of Sobul in a mountainous region of Afghanistan, inhabited by a strange race of winged people known as the "Ibandru". He falls in love with one of them, Yasma, and they marry in a scene of general celebration. When fall comes, however, the Ibandru abandon their valley to fly south with the birds for the winter. Unable to bear the loss of Yasma, Prescott pleads with her to remain with him rather than participate in the traditional migration, with tragic consequences for his marriage.