Theyyam belongs to the shrines and sacred groves of northern Kerala, the region historically called Malabar, and to a religious world that runs alongside the brahminical temple rather than inside it. Its deities are not, for the most part, the great gods of the Sanskrit tradition. They are goddesses of place, serpent deities, ancestors, and above all heroes and heroines who died badly: a woman killed unjustly, a warrior betrayed, a low caste man struck down by a landlord. Their stories are sung in the thottam, the invocation chanted before the transformation, and many of them are stories of injustice that the shrine exists to keep in memory.
The right to perform a given theyyam is hereditary and belongs to particular communities, among them the Vannan, Malayan, Pulayan and Velan, most of whom occupied the lowest positions in the caste order of Malabar and were historically denied entry to the temples of the same villages. That is the fact that gives theyyam its social edge, and it is not a modern reading imposed on the practice: for the hours in which the deity is present, landowners and brahmins of the village stand before a man from a community they would not otherwise touch, and receive his blessing and sometimes his rebuke. The shrine, the season and the hereditary right are all fixed; what the deity says when he arrives is not.