Desire brought them together. Belief and guilt may tear them apart. Middle-aged British woman, Madeleine rents a room to Shibu, a young migrant from Kerala. What begins as a living arrangement quickly becomes an affair. Attraction overrides age, culture and religion - at least at first. But desire quickly collides with reality. Shibu's Catholic beliefs and cultural expectations give rise to guilt and inner conflict. Meanwhile, the ghosts of Madeleine's past begin to resurface, deepening her obsessive behaviours and unsettling the fragile balance between them. They try to pull away. They fail. Again and again, they are drawn back into a relationship that offers hope and renewal, yet seems to trap them both. Song in the Key of Madeleine is a story of love across divides, and of what happens when longing is entangled with faith, memory and fear.