Theyyam also known as Kaliyattam, is popular in North Kerala or the erstwhile Kolathunadu. Theyyam is a ritualistic dance with its rare and grotesque make-up and costume, lively footwork, gymnastic fervor and ritualistic vitality. Theyyam represents a glorious period of folk life in Kerala and the souls of the dead heroes of the land and the gods and goddesses are supposed to come in our midst through the medium of the possessed dancers and converse with us on matters of even contemporary significance. It is the worship of spirits by invoking them to the mortal body of the dancer who impersonates them and gives blessing to the believers.

One of the salient features of Theyyaattam is that the dancers are men in feminine attire wearing colourful costumes and ferocious masks.

The typical waist dress is made out of splices of bamboos or coconut or palm leaves and covered by red cloth. Above the waist dress, the naked body and face is painted with different native colours that differ from Theyyam to Theyyam.

The headgear or Mutis are made out of bamboo splices and wooden planks that are covered with coloured cloth, flowers and coconut leaves. In new Mutis, peacock feathers are also used. Some of the headgears go up to 50 or 60 feet high. Silver and gold is also used in the decoration of Bhagavathi Theyyam.

The female deities wear ornaments and a wooden breast called mularu. All male and female Theyyams wear bangles called Katakam and Chutakam and small anklets on the feet. In the case of Bhagavathis in Roudra mood, (fearful appearance) torches are appended to the waist and the crown produces a terrible appearance.

The pace of the dance is set to the beating of Chenda (drum). The artiste invested by the goddess in his person falls in a trance, dances deliriously to the mounting tempo and conveys, as an oracle, the goddess's acceptance of the vow and blessings or otherwise.

Theyyam incorporates dance, mime and music and enshrines the rudiments of ancient tribal cultures which attached great importance to the worship of heroes and the spirits of ancestors. 'Thudangal' (the beginning) and 'Thottam' (the invocation) are the introductory rituals of the Theyyam or the Thira, as it is known in south Malabar.