Prashanth is an Indian film actor who predominantly appeared in lead roles in Tamil cinema, as well as a few Telugu, Hindi and Malayalam films. The son of actor-director Thiagarajan, Prashanth began his career at 17 by appearing in Vaigasi Poranthachu (1990) and went on to feature in other popular films including R. K. Selvamani's Chembaruthi (1992) and Mani Ratnam's action-comedy Thiruda Thiruda (1993). After a brief career lull, Prashanth appeared in a dual role in Shankar's blockbuster romantic comedy Jeans (1998) alongside Aishwarya Rai. In the late 90s and early 2000s, he featured in a few successful films such as Kannedhirey Thondrinal (1998), Kaadhal Kavithai (1998), Jodi (1999), Parthen Rasithen (2000), Thamizh (2002) and Winner (2003).
Prashanth started off as a leading romantic hero in the 1990 surprise hit Vaigasi Poranthachu. The low budget film was released without much expectation, but its hit music by Deva and galaxy of comedy stars made the film entertaining resulting the successful launch of Prashanth, then he surprised everyone by accepting Malayalam film Perumthachan written by M. T. Vasudevan Nair. His performance as the son of legendary carpentar Perumthachan, played by Thilakan won him rave reviews. The film was a commercial success as well. Prashanth completed Hat-trick of hits with Balu Mahendra' s Vanna Vanna Pookkal. But R. K. Selvamani' s Tamil-Telugu Bi-lingual became blockbusters in both Tamil Nadu and Andhra Pradesh establishing Prashanth as the numero uno Romantic star of South Indian films. Meantime Prashanth's contemporaries Vijay debuted in 1992 and Ajith Kumar made his debut in 1993. Prashanth tasted his first failure in Unakkaga Piranthen opposite Mohini and his Bollywood debut I Love You also bombed in spite of its super hit musical score. Ironically the film was the remake of his debut film Vaigasi Poranthachu. He continued doing the romantic roles in Enga Thambi with Subhashri, Kizhakke Varum Paattu and Rasa Magan. He again teamed with R. K. Selvamani in Kanmani, but this time success eluded them, but Sendhamizh Selvan, which had music by M. S. Viswanathan & Illayaraja as a team, done good business especially in rural centres. Later Tholi Muddhu, the Telugu remake of Hindi blockbuster Dil failed at the box-office as many scenes had continuity issues due to the death of actress Divya Bharti. Bi-lingual film Anokha Premyudh and Mani Ratnam' s Thiruda Thiruda too failed to hit the bulls eye. Prashanth experimented as an actor for the first time as Drag in Aanazhagan directed by his father Thiagarajan, however the film failed to live up to expectations. Later he teamed with Ajith Kumar in Kalloori Vaasal, followed by Krishna and Mannava. Midas touch director Shankar's Jeans ended his search for a superhit after the string of moderate success. He followed the super success once again in Kannedhirey Thondrinal along with Karan and Simran. Agathiyan' s Kaadhal Kavithai too was a success like Jodi and Hello with Simran and Preeti Jhangiani respectively. But Aasaiyil Oru Kadidham and Poomagal Oorvalam failed at the box-office.
His first release of this decade Good Luck did well with good promotions, also his next releases Appu, the remake of Hindi hit Sadak done well while Parthen Rasithen became a super success. The subtle performance as a taxi driver suffering from mental agony due to his sister's death and the lover caught between 2 lady loves were appreciated for both films respectively. But the much awaited Piriyadha Varam Vendum along with Shalini had a delayed release harming its potenial success. He followed with success like Chocolate and Majunu, but director Hari 's debut film Thamizh released along with Vijay' s Thamizhan became a success, but another debutant director Susi Ganeshan' s Virumbugiren had a delayed release resulting in failure in spite of good reviews. Later Sundar C' s Winner became a huge success at the box-office and the credit was given to Prashanth's combination with comedian Vadivelu' s hilarious performance. Prashanth's subsequent releases Jai, Shock and Aayudham fared well at the box office except London which done moderate business. His three films which released in 2006 had all been severely delayed during production and neither of the films made notable impact at the box office. Jambhavan, which released in September 2006, had gone through production hassles notably after the lead heroine Nila had a spat with the producers and delayed the film's shoot. Debutant director's Bhuvanaraja's Adaikalam, a family drama which had been completed the previous year, gained positive reviews but the low key nature of the release hampered any chance of a successful box-office run. Featuring no lead heroine, the film told the tale of an estranged family with Thiagarajan, Saranya and Uma also in the cast and a critic noted that "as a brother and a bitter son, Prashanth has churned out what is arguably one of his better performances His final release of the year was Shiva Shanmugam's Thagapansamy which featured Prashanth in the role of a village do-gooder, with Pooja and Namitha in other pivotal characters. The film opened to below average collections and average reviews from critics, though Sify.com noted to "watch the film for the one-man-show of Prashanth, as he is the only silver lining in a film with a confused and confounded plot." Prashanth had no film releases between January 2007 and April 2011, but was involved in the production of two heavily delayed productions during the period – Ponnar Shankar and Mambattiyan. Moreover he had to face legal issues in his personal life due to his marriage and subsequent court declaration of nullifying his marriage, which made him to take a break. The actor also invested in business opportunities, opening a 12 floor jewellery mart named Prashanth Real Gold Tower at Panagal Park, T Nagar, Chennai in 2008.