'No one remembers when and why I started calling my father Bondhu. It was a strange way to address a father, as rhe word means "friend" in Bengali… As I got older, I became very self-conscious about such an odd name … and yet I cannot explain why I could not switch to the more acceptable Baba or something similar.' Just as Kunal Sen, son of actor Gita Sen and filmmaker Mrinal Sen, was approaching adolescence, his father's cinematic celebrity was reaching new heights at home and the world. In this memoir, Kunal reflects on growing up in a middle-class household in South Calcutta, where his fathers Marxist beliefs and unrelenting urge 'to be challenged and contradicted' often collided with the practical challenges of making a living. Through it all, what emerges is a family's unyielding commitment to the craft of cinema, the risks each of its members took, and their endearing sense of humour. Celebrating Mrinal Sen's birth centenary in 2023, Bondhu takes us on an intimate journey of a son attempting to reconcile his father's public and private selves. After completing his graduate studies in physics, Kunal Sen became interested in computer science, went back to graduate school and then moved to Chicago to obtain a PhD in artificial intelligence. For the next 20 years, he was involved widi various aspects of digital technology, including designing electronic medical systems, writing technical books and, since 1999, heading the technology group at Encyclopaedia Brkannica. Since 2012, he has shifted his primary focus to making art. This is his first book.