Dinanath “Deen” Dutta is the narrator of Gun Island. Originally from Calcutta (Kolkata), he is a rare books dealer of Bangla descent who moved to America as a university student following the death of his first love, Durga. He has lived and worked in the United States ever since, first in a library in the Midwest, and then in New York, where he eventually set up his own place in Brooklyn.

The legend of the Gun Merchant in the book parallels different aspects of each of the central characters’ stories, and Deen is no exception. He keenly feels the lack of romantic love in his life, for he arrived in the United States shortly after Durga’s death. Years later, he is still partnerless. He hopes to begin a relationship with Piya, and although he is initially rejected, the author inserts hints at the end of the novel that this relationship will progress. The Gun Merchant’s legend brings Piya into Deen’s life and facilitates his romantic hopes for the future, for his own adventure is fueled by his pursuit of the legend itself. Ultimately, Deen uses his knowledge of the legend to help Piya trace Tipu through a series of strange coincidences that mirror the Merchant’s story.