Ajith Kumar was born as the middle child in Secunderabad, a city north of Hyderabad to a Palakkad Iyer from Kerala and a Sindhi mother, and was brought up in Chennai, Tamil Nadu. Ajith began speaking Tamil only after entering films. He dropped out of Asan Memorial Senior Secondary School in 1986 before completing his higher secondary. He took up work as a two wheeler auto mechanic, and got himself a driver's licence to coincide with his interests, that of car / bike racing. At 18, Ajith had to take up a job to support his career in racing. Joining as an apprentice, he rose to be a merchandiser with a garment export company, doing small-time press ads and TV commercials occasionally. He had put a lot of money into racing and would borrow tyres from his friends who used to help when the chains wore out as there was no money in racing at that time. Following an accident, several business agencies pushed him into modeling for advertisements in print media. He had to make a choice between films and racing, and as the movies were happening and generating him some money, he began concentrating on it.
Aged 20, Ajith was selected by Telugu film producers, Lakshmi Productions, to star in their film; however shooting was stalled soon after filming began, following the death of the film's director. Ajith then started his film career at the age of 21 appearing in the low budget Telugu film, Prema Pustagam in 1992, which remains his last direct Telugu film to date. His first Tamil film Amaravathi, directed by then newcomer Selva, was a moderate success and his voice was rendered by fellow actor, Vikram. After the release, Ajith whilst training for an amateur motor race, suffered a fall, injuring his back and underwent three major surgeries resulting in a bed rest for one and a half years. Following the injury in 1993, Ajith played a supporting role in the Arvind Swamy starrer, Paasamalargal, before appearing in a supporting lead role in the family drama, Pavithra, which featured him as an ailing patient shown maternal affection from Raadhika.
In 1995, after a supporting role in the Vijay starrer Rajavin Parvaiyile, Ajith appeared in his first major success, Aasai. The film directed by Vasanth and produced by Mani Ratnam, featured him in the lead role opposite Suvalakshmi, whose brother-in-law infatuates about her. The film became a big success and established Ajith as an upcoming actor in the Tamil film industry. He later played the lead in Kalloori Vaasal co-starring Prashanth and Pooja Bhatt. Ajith's second blockbuster came in the form of National Award winning Kadhal Kottai, in which Ajith reunited with Agathiyan, the director of the earlier project Vaanmathi. The film which told the tale of two people falling in unconditional love without seeing each other until the climax. The film paired him opposite Devayani, with Heera Rajgopal, who Ajith fell in love during the making of the project, playing a supporting role.
After the success of his films in 1996, the following year saw a series of five failures, the most notable being Amitabh Bachchan's Tamil production Ullaasam with Maheswari, in which he was paid a salary of Rs. 2 million for the first time. Ajith returned with another successful project in Saran's Kadhal Mannan, with the "masala film" setting the foundations for an expanding fan base. He also rejected roles in Mani Ratnam's Nerukku Ner, which was later played by actors Vijay and Suriya. Following films Aval Varuvala and Unnidathil Ennai Koduthen also became successes, with the latter featuring Ajith in a praised guest role. After a couple of average grossers in Uyirodu Uyiraga and Ramesh Khanna's Thodarum, Sundar C's romantic drama Unnaithedi opposite Malavika became another comeback film and set the tone for a series of big successes. S. J. Suryaah's thriller, Vaali, which portrayed him in dual roles opposite Simran, became his biggest hit til date following its release. The film told the story of a deaf and mute brother setting his eyes on his younger brother's wife, with Ajith's portrayal of the two brothers winning him his first of many awards for Filmfare's Best Actor. Furthermore Ajith's portrayal of the brothers was also praised, with critics claiming that the film was an"instant classic" with Ajith showing that he is a "talented actor". The two following supporting roles in the drama films Anandha Poongatre and Nee Varuvai Ena also brought Ajith plaudits for his portrayals. His final film before the new millennium was another blockbuster, Amarkalam directed by Saran and featuring Shalini, whom he married shortly after the film. Amarkalam told the story of a negelected child who grew up and fails to show feelings of love or affection, becoming a gangster in the process, with Ajith's depiction of his rogue character appreciated by critics.
His next, Mugavaree, won him commercial and critical praise. The film revolved around the life of a struggling music composer who faces sacrifices to proceed in his career. The film featured dual endings, one with Ajith succeeding in his career, the other with Ajith dejected. Ajith's performance was yet again praised with critics from Rediff, claiming that "Ajith is the real winner", drawing an allusion with the film's script, whilst adding that "it is amazing to see how Ajith has grown as an actor. He brilliantly portrays the vulnerable and sad Sridhar". He also appeared in A. R. Rahman's 2000 musical Kandukondain Kandukondain directed by Rajiv Menon. The blockbuster featured Ajith alongside prominent actors Mammooty and Abbas and actresses Aishwarya Rai, Tabu and Srividya. In a similar role to his previous film, Ajith played a struggling film director facing an oscillating relationship with Tabu, with the pair being unanimously praised for their roles. His first failure in eight films, came in the form of the military based Unnai Kodu Ennai Tharuven co-starring Simran.
In 2001, Ajith appeared in Dheena, A. R. Murugadoss's debut film co-starring Laila Mehdin and Suresh Gopi. The film, indirectly marked the beginning of a new image of Ajith, that of an action hero that would appeal to the masses. Furthermore from the successful film, Ajith's nickname in the film, Thala, Tamil for Leader, became a new identity for the actor amongst his fans. In the same year, he was offered a role in Nandha, which he rejected. His next was the much-hyped thriller, Citizen, portraying Ajith in ten different get-ups and it became an above average success at the box office, despite being labelled a disappointment from critics. A role in the family drama, Poovellam Un Vasam followed opposite Jyothika and was a success commercially and critically earning a Special Best Actor Award from the Tamil Nadu State. The year ended off with an appearance in Santosh Sivan's Hindi project, Asoka, in which Ajith appeared in a brief negative role alongside Shah Rukh Khan. 2002 saw Ajith appear in three films, the first two; Red and Raja being average grossers, the former further building up his image as an action hero. The third film, Villain, in which Ajith appeared in dual roles, one as a mentally ill handicap, became a blockbuster and in return earning Ajith his second Filmfare Best Tamil Actor Award.
The following years, from 2003 til 2005, saw Ajith appear in a fewer amount of films due to his career in motor racing becoming more prominent. 2003 saw the release of his long-delayed Ennai Thalatta Varuvala and the police-drama Anjaneya, both failing commercially. In that period, three films namely Kaakha Kaakha, New and Ghajini were turned away by the actor.
His next Jana with Sneha also became a big failure, with the Saran film, Attagasam being his only hit in the period. The film, saw Ajith portray dual roles, with a song, Thala Deepavali penned to promote his action image. In 2005, the failure of the Linguswamy film Ji, despite garnering positive reviews and taking a strong opening, saw Ajith take a sabbatical from acting to re-work his image.
Success and stardom (2006–present)
During 2006, Ajith returned from his hiatus by appearing in P. Vasu's Paramasivan for which he had lost twenty kilograms to portray the lead role. The film enjoyed a moderate success, scoring over Vijay's Aadhi, which also released in the same week, at the box-office. Critics from The Hindu stated Ajith looked "trim and taut" in the film with "only his eyes seeming to have lost some of its sparkle", following the major weight loss. Furthermore, for Paramasivan and his two other projects in 2006, Ajith sported long hair, which was being grown for Bala's project, Naan Kadavul, which Ajith eventually opted out of.
Similarly his next, AVM Productions's, Thirupathi directed by Perarasu performed above average business at the box-office, despite garnering poor reviews, with Rediff critics citing that the film is "anything but sensible" but that Ajith "salvages the situation with a spirited performance". Ajith summed up a successful comeback by the release of his long-delayed film, Varalaru which went on to become his biggest success til date. The K. S. Ravikumar film co-starring Asin, portrayed Ajith in three roles, including that of a classical dancer, with his portrayals being critically praised. Moreover, the film fetched Ajith his third Filmfare Best Actor Award, on its way to becoming a blockbuster. In 2007, media reports hinted that the actor would do a project with Shankar. Ajith's first release in 2007, Aalwar became a debacle at the box-office, with his previous film still continuing to run in theatres even after Aalwar had stopped its brief theatrical run. Kireedam, a remake of the 1989 National Award winning Malayalam film of the same name was released to positive reviews, with the film also becoming a moderate success. During the shoot of the film, Ajith developed a further spinal injury, a recurrence of his problem earlier in his career.