Kumar made his Bollywood acting debut with the 1991 film Saugandh, which was followed by the 1992 thriller film Khiladi. In 1994, his action films Main Khiladi Tu Anari and Mohra which were among the highest grossing films of the year.Later that year, Yash Chopra signed him for the romantic film Yeh Dillagi which was also a success. He received appreciation for his performance in this film, where he played a romantic role which was different compared to his action roles. He would consequently receive his first nominations for Best Actor award at the Filmfare and Star Screen ceremonies. During the same year, Kumar also had success with films like Suhaag and the low budget action film Elaan. All these achievements, promoted Kumar as one of the most successful actors of that year.
In 1995, along with his share of unsuccessful movies, he starred in the third film in his Khiladi series Sabse Bada Khiladi, which was a hit.He proved to have success with the Khiladi series, as in the next year he starred in the fourth successful film with Khiladi in the title, Khiladiyon Ka Khiladi opposite Rekha and Raveena Tandon. The film became one of the highest grossing films of the year.
In 1997, Kumar was seen in a supporting role in Yash Chopra’s hit film Dil To Pagal Hai, for which he received a Filmfare Best Supporting Actor Award nomination. In the same year, he attempted a comedy role with the fifth film in the Khiladi series, Mr and Mrs Khiladi. Unlike his previous films with Khiladi in the title, the film failed commercially. In the same way as this film, his next Khiladi releases in the following years went on to fail at the box office. In 1999, Kumar received critical acclaim for his roles in the films Sangharsh and Jaanwar. Whilst the former did not make a profit at the box office, the latter turned out to be a success.
Kumar on the sets of Heyy Babyy
In 2000, he starred in the comedy Hera Pheri (2000) which was a commercial success. He also starred in the romantic film Dhadkan later that same year which performed moderately at the box office. That same year, he performed some of his most dangerous stunts in Khiladi 420, where he climbed a running plane, stood on top of the plane flying a thousand feet in the air, and jumped from the plane onto a hot air balloon. In a later scene, he is also seen being chased by a car, dodging bullets, jumping off buildings, and climbing walls. In 2001, Kumar played a negative role in the film Ajnabee. The film won him much acclaim as well as his first Filmfare Award for Best Villain. Kumar played a role as role as a blind man in Aankhen.
Following Hera Pheri, Kumar starred in a number of comedy films, including Awara Paagal Deewana (2002) and Mujhse Shaadi Karogi (2004).and Garam Masala (2005). The films succeeded at the box office and his performance in the latter earned him his second Filmfare Award, for Best Comedian. Apart from his action, comedy and romantic roles, Kumar displayed a flair for dramatic roles in films such as Ek Rishtaa (2001), Aankhen (2002), Bewafaa (2005) and Waqt: The Race Against Time (2005)
In 2006 he starred in a sequel to Hera Pheri titled Phir Hera Pheri. As was the former, the sequel became a huge success at the box office. Later that year he starred alongside Salman Khan in the romantic musical Jaan-E-Mann. The film was a well anticipated release, and despite receiving positive reviews from critics, did not do as well as expected at the box office. Though the film under-performed, his role as a shy, lovable nerd was praised. He ended the year with the comedy Bhagam Bhag, which was a success. In that same year, he led the Heat 2006 world tour along with fellow stars Saif Ali Khan, Preity Zinta, Sushmita Sen and Celina Jaitley.
2007 proved to be Kumar’s most successful year during his career in the industry, and as described by box office analysts, “probably the best ever recorded by an actor, with four outright hits and no flops. His first release, Namastey London, was critically and commercially successful, and his performance earned him a Best Actor nomination at the Filmfare. Critic Taran Adarsh wrote of his performance in the film, “he’s sure to win the hearts of millions of moviegoers with a terrific portrayal in this film. His next two releases, Heyy Babyy and Bhool Bhulaiyaa, were box office successes as well Kumar’s last release of the year, Welcome, did extremely well at the box office, receiving a blockbuster status and simultaneously becoming his fifth successive hit. All of Kumar’s films which released that year did well in the overseas market as well
Kumar’s first film of 2008, Tashan, marked his comeback to the Yash Raj Films banner after 11 years. Although much anticipated by the public, the film was a critical and commercial failure. His second film, Singh Is Kinng was a huge success at the box office and broke the first-week worldwide record of Om Shanti Om, the previous highest figure. His next film was the animated film Jumbo. The year also saw Kumar making his small screen debut as the host of the successful show Fear Factor – Khatron Ke Khiladi. He later returned to host the show’s second season in 2009.
In 2009, Kumar featured opposite Deepika Padukone in the Warner Bros.-Rohan Sippy production Chandni Chowk to China. Directed by Nikhil Advani, the film was a critical and commercial failure at the box office. Kumar’s next release was 8 x 10 Tasveer. Directed by Nagesh Kukunoor, the film was a critical and commercial failure. His next release was Kambakkht Ishq. Kumar’s film Blue was released on 16 October 2009. Blue collected about Rs. 42 crores at the box-office. His release in 2009 was Priyadarshan’s De Dana Dan.
He then appeared in the 2010 comedy, Housefull, directed by Sajid Khan which garnered the second-highest opening weekend collection of all time. Kumar’s next release was Khatta Meetha, directed by Priyadarshan which was an average grosser. He also appeared in Vipul Shah’s Action Replayy, which was a box office failure