Kumar started his acting career as a stage actor, starting with
IPTA in
Bombay and later joining the Indian National Theatre. Even as a stage actor, he had a penchant for playing older roles; at age 22, he played an old man in an adaptation of
Arthur Miller's All My Sons. In the following year, in the play
Damru directed by
A.K. Hangal, he again played the role of a 60-year-old with six children. His first film as a protagonist was in
Nishan (1965). In 1968, he acted alongside
Dilip Kumar in
Sunghursh. He also starred opposite
Shammi Kapoor and
Sadhana in the hit film
Sachaai (1969). He starred in the 1966
Gujarati film
Kalapi, which was based on the poet
Kalapi's life, with him playing the title role,
Padmarani playing the role of his wife, Rama and
Aruna Irani as the love interest. The film was directed by
Manhar Raskapur. Later
Aruna Irani worked with him in another
Gujarati film,
Mare Javun Pele Par (1968). In 1970, the movie
Khilona, which was the remake of
Gujarati film
Mare Javun Pele Paar (1968), brought Kumar national recognition. In 1972, he played in an Indo-Iranian film,
Subah-O-Shaam. This was when the director
Gulzar first spotted him. Later he cast Kumar in the roles of older men in 4 films
Parichay (1972),
Koshish (1973),
Aandhi (1975) and
Mausam (1975).
Gulzar cast Kumar in the roles of younger men in the films
Angoor (1981) and
Namkeen (1982). He won the
BFJA Awards for Best Actor (Hindi) for his portrayal of a deaf and mute person in
Koshish opposite
Jaya Bhaduri. He reached to his success when he starred in the box office hits
Seeta Aur Geeta (1972),
Manchali (1973) and
Aap Ki Kasam (1974). In 1973, he made a guest appearance during a song in a
Tamil movie,
Bharatha Vilas (1973). He performed in nine movies directed by
Gulzar.
Hrishikesh Mukherjee directed him in
Arjun Pandit, for which he won the Filmfare Best Actor Award. He did three films opposite famous
Tamil actress
L. Vijayalakshmi, including
Husn Aur Ishq and
Badal which became hits. Their first film was
Alibaba Aur 40 Chor which was unsuccessful. His
Raja Aur Runk, released in 1968, was a great success. He did
Kangan,
Rivaaj,
Zindagi,
Be-Reham,
Archana and
Do Ladkiyan opposite
Mala Sinha. He did
Priya,
Anubhav,
Gustaaki Maaf,
Bachpan and
Khud-Daar with
Tanuja. He was paired with
Raakhee in
Angaare,
Paras,
Trishna,
Shriman Shrimati and
Hamare Tumhare. His hits with
Leena Chandavarkar included
Apne Rang Hazar,
Manchali and
Anhonee. He was paired regularly with
Sulakshana Pandit in films such as
Uljhan and
Waqt Ki Deewar and with
Moushumi Chatterjee in
Itni Si Baat and
Daasi. The producers and directors of the South wanted to remake their
Tamil and
Telugu films in
Hindi with either
Kumar or
Rajesh Khanna in lead. It was these
Hindi film remakes which elevated the success in his career.
Khilona and its
Tamil version
Engirundho Vandhaal were made simultaneously.
Navarathri was remade as
Naya Din Nai Raat.
Kumar reprised the role played by
Thengai Srinivasan in
Yehi Hai Zindagi which was a remake of
Kaliyuga Kannan. He starred as the lead
Shaandaar (1974) which was a remake of
Kasturi Nivasa with
Kannada actor
Dr. Rajkumar in the lead.
Kumar enacted the role played by
AVM Rajan in
Anadhai Aanandhan, in its
Hindi version
Chanda Aur Bijli.
Gnana Oli was remade as
Devata in 1978 with
Kumar reprising the role originally played by
Sivaji Ganesan. He also acted in
Swarg Narak (1978) the remake of
Swargam Narakam. He played the role which
N.T. Rama Rao did originally in
Devina Chesina Manushulu, in its
Hindi version
Takkar in 1980.
Tayaramma Bangarayya was remade as
Shriman Shrimati in 1982,
Raman Ethanai Ramanadi was remade as
Raam Kitne Tere Naam in 1985. Kumar reprised the role played by R.Muthuraman in
Alukuoru Aasai in its Hindi remake
Itni Si Baat in 1981. Sivaji Ganesan gave Kumar a role in his own home production
Gauri (1968), which was a remake of
Shanti (1965). The role played by S.S. Rajendran in
Shanti was re-enacted by Kumar in
Gauri. Northern Indian producers and directors cast Kumar primarily in supporting roles in films like
Khud-Daar,
Sawaal,
Zabardast,
Hero, and
Silsila. Sanjeev Kumar's excellent comic timing entertained audiences in films such as
Seeta Aur Geeta,
Biwi O Biwi (1981),
Pati, Patni Aur Woh,
Angoor (1982) and
Hero (1983). His performances in films such as ,
Grihapravesh,
Chehre Pe Chehra,
Suraag,
Sawaal and
Yaadgaar were appreciated by critics. Kumar always demonstrated a willingness to take on unconventional roles that challenged him as an actor. His role as Mirza Sajjad Ali, a chess-obsessed Lucknowi (citizen of
Lucknow), in
Satyajit Ray's classic
Shatranj Ke Khilari (1977) exemplified that aspect. His best-remembered roles were in the blockbuster films
Sholay (1975) and
Trishul (1978). His portrayal of the character
Thakur, from
Sholay was regarded as one of his stellar performances. In
Naya Din Nayi Raat (1974), Kumar reprised nine-roles. This film enhanced his status and reputation as a serious actor in
Bollywood. He stood his ground against leading superstars such as
Rajesh Khanna in
Aap Ki Kasam;
Amitabh Bachchan and
Shashi Kapoor in the
Yash Chopra multi-star cast film
Trishul (1978) and Dilip Kumar in
Sangharsh and
Vidhaata (1982). He did many regional films in different languages including
Marathi,
Punjabi,
Tamil,
Telugu,
Sindhi and his mother land
Gujarati. In 1980, he starred in the
Punjabi movie
Fauji Chacha. He also made guest appearances in two Tamil films,
Bharata Vilas and
Uyarndhavargal (a remake of
Koshish). == Personal life ==