Powered by a strong desire to become an actor, Rajinikanth went to Madras, the tinsel town of Tamil Cinema. He was helped by a friend to join the Madras Film institute and completed his acting course in 1974.

Rajinikanth got his first break in movies when he played a small role in kannada movie "katha sangama" of late director Puttanna kanagal. Later he in tamil he played as cancer-patient in the movie Apoorva Raagangal (1975). This film was directed by K. Balachandar, whom Rajinikanth considers his mentor, and who named him Rajnikanth. This movie also starred Kamal Hassan in the lead role, who became one of his closest friends. The movie that fetched Rajinikanth a wide recognition was Moondru Mudichu (1976), in which he played the role of a cruel womanizer. He followed it up with movies like 16 Vayadhinile , Gayathri, which cast him in villainous and anti-hero roles. Director S. P. Muthuraman first experimented with him in a positive role in Bhuvana Oru Kelvikkuri, in which Rajinikanth played a villain in the first half and a refined man in the second. Then Rajinikanth slowly moved on to playing positive and character roles in movies like Mullum malarum, Arilirundhu arubathu varai. Films Billa, Pokkiri raja and the like saw him playing stylish action roles while Murattu kalai, Payum puli and Moondru mugam took him to dizzy heights. He was also good at comedy as can be seen in Thillu mullu (1981). But the most unique among his movies was Sri Raghavendra (1985) "his 100th film"which was a biographical portrait of Hindu saint Raghavendra Swami.Some of the best dramatic movies of Mr.Rajinikanth would be pudhu kavithai and aarulirundhu arubadhuvarai.In pudhukavithai,he depicts a person who has lost his lady love and roams as a drunkard in the roads of bangalore,and their reunion is picturised in the best way possible.The sweet romance feel is given by none other than the Maestro illayaraja.

The late 1980s saw him doing more and more action oriented family entertrainers like Velaikkaran, Manidhan, Dharmathin thalaivan, etc., and it was never looking back for Rajinikanth. His movies made in the 1990s became mass blockbusters. Some of these include Annamalai, Baasha, Padayappa. These movies also had a tinge of politics.

His Latest movie was Chandramuki (April 2005) which is a remake of the malayalam blockbuster movie "Manichitrathazhu" starring Superstar Mohanlal (also remade in Kannada as "Aaptamithra"). Chandramuki has broken all the box office records of all movies ever made in any Indian film industry. It made the records created by Hindi movies--like Sholay, Hum aapke hein koan etc-- look silly. It was made after his previous movie Baba (2002) was not so successful. His next film Sivaji is being directed by S. Shankar.

Rajinikanth is popular for his flamboyant dialogue delivery and characteristic mannerisms. While contemporary actor Kamal Hassan selects performance oriented roles, Rajinikanth's movies has been mass entertainers. His movies invariably has a 'good win over evil' theme with entertaining action sequences, catchy songs and good natured humour, which makes his films liked by people of all age groups and all walks of life.

Rajinikanth has acted in over 170 films including movies in Telugu, Kannada, Malayalam, Hindi and Bengali. He has also acted in one Hollywood movie (Blood stone in 1988). He has acted along with notable actors like Sivaji Ganesan, Amitabh Bachchan, Kamal Hassan, Mammooty and Sridevi. He has worked with famous directors like Mani Ratnam and Bharatiraja.

He was rated as one of the most influential persons in South Asia by Asiaweek.

Rajinikanth, as he's popularly known by fans, his movies are known for their punch dialogues, which are "one-liners" in the movie and repeated by him in the movie after/ before a cinematic triumph. Popular Lines:

• " Naan oru dhatavai sonna, Adhu nooru dhatavai sonna madhiri" (roughly translates to - "If I say it once its equivalent to saying it a hundred times") - in the movie "Baasha"
  
• "Aandavan Solran Arunachalam Mudickiran" (translation - "God tells me, Arunachalam finishes it") -in the movie "Arunachalam".
  
• "Adhighama Aasappadra Aambleyum Adhighama Kovappedra Pombleyum Nalla Vaazhntha Charithrame Kedayadhu" (translation - "History depicts that-Man who is greedy and woman who has more anger hasn't lived a pleasant life") - in the movie"Padayappa".
  
• Valli - Nee virumburavalai kattikiruthai vida unnai virumburavalai kattikitta un vazhkkai santhoshama irrukkum.. Valli - It'll be better to marry a girl who likes you than a girl you like most "Valli"
  
• Annamalai - Naan solrathaiyum seiyven.. sollathathium seiyven... Annamalai - I'll do what I say, and also what I don't say "Annamalai".
  
• "Naan solratha thaan seivan, seiratha thaan solluven" (translation- I do what I say, I say only what I do) - movie "Manithan".
  
• Uzhaippali - Nethu naan coolie.. enniku naan nadigan.. naalaikku... Silaber solranga naan eppadi varuven appadi varuven.. naan eppadi varuvennu andavanukkum mattum thaan theriyum.. Uzhaippali - Yesterday I was a coolie, today I'm an actor, tomorrow...people may say what they want. But what I'll become, only god knows "Uzhaippali"
  
• "Laka Laka Laka Laka Laka Laka....."- movie "Chandramukhi".
  
• "Idhu Eppadi Irukku" (translation- How is it?) - movie "16 Vayadhiniley".
  
• "Yaen paera kaettaa, vaiyithila yirukkira pulla, oru kaiyaala than vaaya moodi kittu, matha kaiyaala thaan amma vaaya moodum".(translation - If my name is heard, baby in his/her mothers womb would close it's mouth with one hand and close the mouth of his/her mother's mouth with the other hand) - in the movie "Moondru Mugam".
  
• Muthu - Naan eppo varuven eppadi varuvennu yarukkum theriyathu...eppo varunumo appo correctaa varuven... Muthu - When I will make an entrance, where and how.. nobody will now. But when I do make one, it will be at the right time. "Muthu"
  
• "Naan Baba, yaentha pakkamum saaiyaatha Baba" (translation- My name is 'Baba', not a lap dog) - movie "Baba".
  
• "Anger is the reason for all miseries, One should know how to control it, otherwise life will become miserable" - "Padayappa".
  
• Padayappa - En Vazhi Thani Vazhi... "Padayappa".
  
• "Aasanja adikirathu wungga policy, aassaiyamma adikirathu Baba policy" - "Baba"
  
• "Gatham Gatham, Mudinjathu Mudinji Pochi" - "Baba"