For nearly two decades, the writing on the walls of Kolkata belonged exclusively to the Trinamool Congress (TMC). Mamata Banerjee, the mercurial streetfighter of Indian politics, had fashioned an empire that seemed entirely impervious to the saffron wave sweeping through India’s Hindi heartland. Yet, the high-stakes political tectonic shift in May 2026 shattered that illusion of invincibility.