Calus is a protection, healing, and fertility ritual. Iele (They), Mandrele (Beauties) are female demons and were supposed to punish people around Rusalii (Pentecost) who did not respect the interdiction to work on special days honoring the Iele (They). Calusarii are invested with supernatural powers to protect the populace. The Calus dance alone demands a very high degree of agility, power and endurance.

The calusari team is composed of an odd number of men, regardless of age or marital status. There is a hierarchy of responsibility: vataful din coada (the leader at the tail end), the ajutorul de vataf (chief's assistant) and the vataf (chief). Another important member is mutul (the mute) who wears a mask, carries a red painted wooden sword, and has a red wooden phallus attached to his belt. With gesture and pantomime he leads the ritual acts and also plays the comic. Each calusar carries a stick.

The raising of the flag or the binding of Calus takes place on Saturday evening. The ritual is enacted in secret outside the village in places where Iele are said to reside. Until the actual raising of the flag everything is done in silence. The flag is attached to a pole and consist garlic, wormwood and stalks of green wheat wrapped around with a white linen hanf towel. It stands for the magical Calus power and is the symbol of the group's solidarity. The second episode consists of a suite of Calus dances. The third and final episode is yhe burial of the flag. It is carried out in the same location as the first and is meant to disband the corps, release the calusari from their oath, and reintegrate them into normal life.

The calusari (pronounced "kurl-oo-shah") is a traditional Romanian folk dance which bears a close resemblance to the English morris dance and originally derives from Southern Romania. The word "calusari" means "horse men". The dance is thought to be derived from a pre-Christian fertility ritual and is said to bring luck, health and happiness to the villages in which it is danced. Dancers wear white trousers and white tunics, with brightly coloured ribbons streaming from their hats. Bells are attached to their ankles, and dances include the use of sticks held upright whilst dancing, or pointing at the ground as a prop. Like many morris dance sides, the calusari dancers include a fool, known as the "nebun".

Men's group dances with the key features of the ritual dances are found along the Carpathians and in Transylvania. The Carpathian variants such as Trilisesti and Tantaroiul from Moldavia and Barbatescul and De sarit from Maramures… include only the most basic features whereas the De bata, Haidau, and Fecioreasca of Transylvania are very close to the Caluseri with the addition of more complex later developments.
The Whitsun Festival is the time for the Calush, "the little horse" dance. It is not only part of an ancient fertility rite but also a polished performance by professional Romanian dancers called "calushari" which has won world reputation.

This dance was declared by UNESCO part of the cultural patrimony of the world. It is also named "the fastest dance in the world. Don't be fooled by the lack of the "tapping" sound - these dancers wear soft shoes, very similar to the Native American mocassins.