Answer
The answer is Thadaiyara Thaakka, which marked Nayanthara's debut in Tamil cinema in 2006. This romantic comedy film, directed by G. Nagaraj, introduced Nayanthara as the female lead opposite Vimal. Despite its mixed critical reception, Thadaiyara Thaakka played a significant role in launching Nayanthara's successful career in the Tamil film industry.