Prior to directing films, Vijay was a successful advertisement filmmaker with the Mumbai-based banner Venus Productions, completing more than 100 ad films. His State Bank of India commercial won CNBC’s Best Corporate Advertisement Award in 2009. Vijay has claimed that "advertisements teach you how to translate a story idea onto screen with maximum impact in minimum time" and is influenced by the ad works of Priyadarshan, Prahlad Kakkar and Babu Shankar. In 2003, he began his career in feature films by joining Priyadarshan as an assistant director in his films.
He made his directorial debut with Kireedam in 2007, a remake of the 1989 film of the same name directed by Sibi Malayil and written by A. K. Lohithadas. Vijay's version featured Ajith Kumar in the lead role with Trisha Krishnan, Rajkiran, Saranya and Vivek also a part of the cast, while the cinematographer was Tirru, music was composed by G. V. Prakash Kumar and the film was edited by Anthony. Vijay revealed that he "reworked about 80 per cent" from the original version. The film opened to positive reviews with a critic from Sify.com citing that "Kireedam is quality cinema, one that is daringly different from the run-of-the mill films" claiming that Vijay had "a lot of guts and conviction to make a realistic film". The reviewer from The Hindu also praised the film labelling that "Vijay has neatly packaged a strong storyline with a sensibly balanced mix of sentiment and action", but claimed that "Vijay could have worked on the lead character more". The final scene in the film was changed after release from a sad to an upbeat ending after the producers felt that the original scene may keep audiences away. The film consequently went on to become a profitable venture at the box office. Vijay then returned to work as an assistant to Priyadarshan in his award-winning Kanchivaram by helping with the dialogues and described his work in the project as "a liberating experience".
Priyadarshan then approached Vijay to remake the Hindi film Khosla Ka Ghosla in Tamil under his production house and hence they collaborated to make Poi Solla Porom. The film was completed within 34 days, with a cast containing veteran actors such as Nassar and Nedumudi Venu as well as relative newcomers including Karthik Kumar and Piaa Bajpai. The film also became one of the first ventures in Tamil cinema to feature a promotional song, with Vijay maintaining that the song reflected the story of the film. The film won above average reviews from critics with The Hindu citing that "Vijay’s dialogue, both humorous and thought-provoking, tickles the viewer almost throughout" and that "Vijay has understood the pulse of the audience even while sticking to his stand of providing standard fare".
Vijay revealed that Madrasapattinam was supposed to happen later in his career, but the intervention of producer Kalpathi S. Aghoram of AGS Entertainment realized the viability of the film earlier. Vijay had first explored the script in his college days and drew inspiration from an English professor, who used to talk to them about the freedom movement a lot. Vijay visualized the people, who lived in the pre-independence period of India and explored the concept of how it would have been, if an English girl fell in love with an Indian boy, laying the foundations for the script. The script took six months to write with the help of leading Tamil writer Prabanjan. He also visited independence veterans to understand the history of the city of Madras between 1945 and 1947. Arya was finalised to play the lead role and English Miss Teen World winner Amy Jackson was selected after Vijay found a picture of her through the internet. Despite being a period film, the film was finished in eight months and released in July 2010.
The production of the film took five months from start to finish, however, Vijay claimed that the film had been in his plans for four years, but he waited for Vikram to give him dates. Amala Paul was selected after Vijay was pleased with her award-winning work in Mynaa. Sara had appeared in a commercial for Vijay when she was two but he then lost touch with Sara's family, before he met them and cast Sara in Deiva Thirumagal, following a visit to Mumbai.
Vijay directed the Harris: On The Edge concerts by music composer Harris Jayaraj.
In February 2016, he was named as a director of Prabhu Deva's upcoming trilingual film Devi opposite Tamannaah which will be made in Tamil, Telugu and Hindi. This marks his debut in Telugu and Hindi languages.
Vijay has described that he wants his audience "to immerse themselves" in his films and hence uses scenes which reflect the local culture, describing his scenes should mirror society and "lend it an element of timelessness". He revealed that while constructing a film he "first thinks of the plot, then the screenplay and then the characters", and tries to portray human values in his films.
He has expressed that he prefers "to mould actors" telling them to react and not act, drawing such inspiration from the work of Priyadarshan.
Furthermore, Vijay has showed interest in training people and mentoring their careers, citing that he likes to be the oldest member of his crew. His films have a "regular crew" which includes cinematographer Nirav Shah, music director G. V. Prakash Kumar, production designer Selva Kumar and editor Anthony.
On 26 April 2014, Vijay said that he was in a relationship with actress Amala Paul. On 7 June 2014 he got engaged to Amala in Aluva, Kochi. The couple got married on 12 June in Chennai. In July 2016, they decided to separate, and in February 2017, they were declared officially divorced.