Piya is a scientist who studies marine mammals and comes to the Sundarbans to study a rare dolphin. Though she was raised by Bengali parents, she grew up in the United States and does not speak Hindi or Bengali, even though she is working in a very remote part of India where almost no one speaks English. Kanai, on the other hand, is a translator from New Delhi who goes to the Sundarbans to visit his aunt.
Even though Kanai speaks six languages, he and Priya are faced with trying to communicate with the Sundarban locals who do not speak either of their languages. Priya, for example, realizes that she does not necessarily need spoken or written language to communicate with someone. She can communicate at least somewhat with the personnel on the Forest Service boat she works on, but she still feels as though she is not really being listened to. When she meets Fokir, a local fisherman who does not speak her language, she can actually communicate with him better because the two share some form of connection. Priya's journey suggests that emotional and visual language can be even more effective than written and spoken language.
Kanai also undergoes a transformation because of language. Kanai comes to understand the limits of spoken and written language. Though Kanai can speak six languages, his skill does not really help him much in communicating with the local Sundarbans. Fokir explains that language is emotional and can almost conjure things. For example, saying the word "tiger" may be enough to summon the animal. When Kanai sees a tiger, he is so terrified that he cannot even articulate what it is. Fear, Kanai realizes, is like language in that it must be learned and used to make sense of the world around you.