In Sundarban, Baanbhashi village, Amartya the school teacher receives sudden visits from a boy named Duru Duru. When he sees human beings lying, his heart quivers, his chest hurts. Somewhere in this world, there is a fog-wreathed island where grows the medicine for his ailment, the leaf of a tree. The tree is called snake-tree. In the land and village, it is monsoon, drenched by torrential rain and storm. The snake-tree will shed a leaf this very month. But Duru Duru is not happy about this, he is anxious. Because, seven hundred years ago, with the shedding of the first leaf of the snake-tree, human beings began telling lies. If such a thing happens again, human beings will commit more ills, will tell more lies. Duru Duru thinks to himself, he must stop the shedding of a leaf at all costs. But, when he saw the island with the snake-tree, in another lifetime long ago, he cannot recall. He cannot remember the way. What can he do? Tucked away among mountain ranges, the birds of the Panchhiped tree in Pakhigram village know the way. Many eons back, a leaf of the snake-tree was caught before it could touch ground, in the beak of one such bird. The breeze from that leaf has kept the birds and insects of the forest from ever telling a lie. Duru Duru understands the language of the birds of Panchhiped, they will take him there. On that day a great storm broke over Sundarban with darkened skies over the river. Letting go of Amartya's hand, Duru Duru embarks into the storm. Can he stop the leaf of the snake-tree from falling to the ground?