Fluid identities and exchanges between Christians and Hindus have long marked India’s coastal South. After the 2004 Indian Ocean tsunami, however, all differences were momentarily leveled as waves indiscriminatingly killed more than 8,000 people in Tamil Nadu alone. A close ethnographic account of the immediate responses of local people and religious leaders in the face of this acute loss and suffering bespoke a shared sense of humanity and even erasure of religious and caste difference. Over the fifteen years following the tragedy, however, as church leaders, foreign investors, and politicians tried to make the most of the disaster, a darker picture unfolded. The ocean’s killer waves receded only to make room for new tides of money and competition, renewing differences and threatening earlier religious fluidity. The rupture between the Indian and Burmese plates rippled into social ruptures as human need, greed, and tribalism remade the religious and environmental landscape.