The triumphant smile of the glittering goddess Amman is visible from quite a distance down the Old Mahabalipuram Road in South Chennai. Propped up on bamboo sticks and metal wires, a 50-foot image of the deity studded with serial lights sits triumphantly with one foot on the decapitated head of a slain demon.

Such luminous images are a common sight temples across Tamil Nadu at this time of the year. During the Tamil months of Aadi (which runs from July 16-August 16 this year) and Avani (from August 17-September 16), various communities that live around the temples pick three days on which to conduct their festival or thiruvizha for Amman, who is a representation of Parvati.

Images of the goddess and other deities are an essential part of the celebrations.

In Tiruvalluvar Nagar, the Mundakanni Amman temple has been organising a festival in the fifth week after the beginning of Aadi for the past 31 years. The celebrations start with devotional songs and short plays, followed by popular, fast-paced Tamil film songs to which men dance vigourously.

“Everybody waits for this time of the year,” said Sarath Kumar, a resident of the neighbourhood. “Everyone takes leave from work for an entire week during the festival, since all celebrations go on late into the night.”

The Tiruvalluvar Nagar temple has spent Rs. 50,000 just on the decorative lights. Even though the temple lies on an interior road, the gigantic images of the deities glow along the main road, as is the practice with many other shrines in the city.

"Our forefathers have always put up these decorations," said Kumar. "We are just following the tradition. In the villages, the light setting is even grander."

T Raghu, an electrician who has been in the business for 12 years, explained how these intricate decorations are made.

First, a picture of the deity is sketched out in chalk on the ground. Then, bamboo is cut to form a frame. The serial lights are placed along the outline of the picture.

In some cases, electricians are both the artists as well as the technicians. But nowadays, electricians tend to outsource the artistry, said Raghu.

These electricians are part of the retinue of staff employed by the decorators who have been contracted by the temple authorities to handle the arrangements for the festival. In addition to ensuring the lighting, contractors also handle the flowers, tents, seating as well as the sound system.

"Only with these lights will there be a festive look," said S. Krishnamoorthy, a festival organiser at the Mundakanni Temple. "It is so bright, it feels like daytime."

But it is not only the Amman temples that are lit up during festivals. Along the same stretch in South Chennai, figures from the Bible glimmer in the darkness.