Later that year, he appeared in another action masala film Silambattam. In 2008, he starred in the action masala film Kaalai, which was a flop. He next starred in and directed Vallavan (2006), as well as writing its story, screenplay and co-dialogue. This was the second time that Simbu and Jyothika worked together after the success of Manmadhan (2004). In 2006, he starred in Saravana, directed by K. Silambarasan's first release in 2005 was the film Thotti Jaya, directed by V. His final release in 2004 was Manmadhan, co-starring with Jyothika for the first time, and the film became a turning point in his career. Divya Spandana, played his love interest. After this, Silambarasan starred in Kuththu, a remake of the Telugu film Dil. Silambarasan had three releases in 2004 the first was Kovil which deals with the relationship between a Hindu boy and a Christian girl. His second film was Dum (2003), which was loosely based on Jagannadh's 2002 Kannada film Appu.
Silambarasan played his first protagonist role in Kadhal Azhivathillai (2002), directed by his father. He then started acting in his father's movies from 1995, including Thai Thangai Paasam, Oru Vasantha Geetham, En Thangai Kalyani, Enga Veetu Velan, Monisha En Monalisa, Oru Thayin Sabhatham, Samsara Sangeetham, Shanti Enathu Shanti, Pettredutha Pillai, Thiruvalla and Sabash Babu. Silambarasan appeared as a baby in the film Uravai Kaatha Kili held by his father T Rajendar.
The singer include the film's lead actor Silambarasan, Anushka Manchanda from the girl-pop group Viva! and rapper Blaaze, who all sung for the first time under Raja's direction. The lyrics were penned by Vaali, Snehan, Pa. The soundtrack, composed by Yuvan Shankar Raja, released on 1 July 2004 and features 6 songs. Mandira Bedi as Psychiatrist (special appearance).Brinda Parekh as Train Passenger (guest appearance).Guhan Shanmugam as Madhan Kumar's college rival.Sathyan Inspector Shakthi (Deva's assistant).Silambarasan as Madhan Kumar ( Manmadhan) and Madhan Raj ( Motta) - dual roles.The film ends with a message that even if Manmadhan has escaped the clutches of the police, he would still answer for his actions before the law. Hence, Madhan Kumar concludes that avenging his brother's death is more important, and only God can judge his actions. He also exclaims that if his brother had loved a girl like her, he would also have lived happily and would have married her. The movie ends showing that Madhan Kumar indeed loves Mythili for her innocence and good demeanor, but cannot and will not reciprocate her feelings.