Triggered by the US-backed Pakistani junta's brutal measures against the Bengalis, Sheikh Mujibur Rahman proclaimed the independence of East Pakistan on 26 March 1971. They needed the world's support, and India was their first ally.

The Border Security Force (BSF), an elite Indian force, was only five years old at the time and became central to India's sustained military response in East Pakistan for nine months, until the alliance of Indian and Bangladeshi forces won Dacca. The BSF's founding chief, K.F. Rustamji, and his men went beyond their charter of policing borders to respond to one of the world's worst humanitarian crises that was unfolding right next door to India. For nine months, till the 1971 India-Pakistan war, they covertly gave support to the forces of resistance, through clandestine missions and black ops deep in East Pakistan, while diplomats and politicians primed the world for the war. They welcomed democratically elected politicians and helped establish them as the government-in-exile, installed a clandestine radio station, triggered the defections of East Pakistani diplomats and foiled the Pakistan Army's tactical trump card to damage the Indian Air Force bases.

With access to classified records and through exhaustive interviews with surviving veterans, award-winning investigative reporter Ushinor Majumdar has crafted this first comprehensive historical account of the BSF's role in the Bangladesh liberation war, which changed the course of South Asian history.