Based in Brooklyn, Deenanath “Deen” Datta is a dealer of rare books and Asian antiquities who is originally from Calcutta (Kolkata). While in Calcutta (Kolkata) for business one winter, he runs into a distant relative, Kanai Dutt, who mentions a Bengali folk figure, “Bonduki Sadagar” (the Gun Merchant). Deen notes that the story is similar to the legend of Chand Sadagar, a merchant who fled overseas to escape the wrath of Manasa Devi, the goddess of snakes and poisonous creatures. The relative tells Deen that the Gun Merchant is connected to a shrine in the Sunderbans, the mangrove forests in the Bay of Bengal. Kanai’s aunt, Nilima Bose, has been to the shrine and wants to discuss it with Deen. Kanai also gives Deen the phone number of a Bengali American marine biologist named Piyali “Piya” Roy, who teaches in Oregon but visits for the winter and stays with Nilima. Because Nilima is a formidable and wealthy figure, Deen cannot ignore her request to meet, so he calls Piya and sets up a meeting. Piya greets Deen at Nilima’s house; Nilima reveals that Piya’s research is what first brought her to the Sunderbans.