Directed by Rajen Tarafdar, Ganga focuses on the difficult lives of the fishermen’s community along the banks of the river. Panchu, a poor fisherman, lives with his wife and nephew Bilash. Bilash is a rash young man, often embroiled in fights with the other fishermen and the village moneylender. He is also a notorious ladies’ man. Bilash expresses his wish to go to sea, but Pachu and his wife are worried about his temperamental nature. He reminds Pachu of his deceased elder brother, an equally adventurous and volatile man. To rein Bilash in, Pachu’s wife suggests that they marry him off. Pachu agrees to be married when he returns from the river.
During fishing season, the fishermen leave the village for the banks of the river. Pachu and Bilash arrive on the riverbanks with them. Initially, things go their way and they catch plenty of fish. However, they are forced to sell their catch to Damini, the moneylender, to pay off their debts. Meanwhile, Damini’s granddaughter Imi falls in love with Bilash. Pachu warns Bilash against getting involved with her, but he falls for her as well. Pachu’s fortunes start taking a turn for the worse when his catch is affected by another fisherman’s nets. Pachu starves to death. Before his death, he exhorts Bilash to fulfil his wish of going to sea.
Bilash returns to the village, where he informs the villagers of his intent. Bound by superstition, they caution him against such a rash decision. Bilash inspires them to set their fears aside, and leads them to the sea. He returns to Imi to take her with them on their voyage. Damini, in the interim, has warned Imi of the consequences of falling in love with a fisherman. Imi realizes the gap that separates them, and she gives him all her savings and jewels, asking him to leave her behind. He promises to return to her, and rows away as she stands at the shore.