[1] He worked as an associate director on films including Bhuvana Oru Kelvi Kuri (1977), Aarilirunthu Arubathu Varai (1979) and Priya (1978).
[2][1] As a director, Rangarajan subsequently collaborated with Kamal Haasan on a number of successful films including Kalyanaraman (1979), Meendum Kokila (1981), Kadal Meengal (1981) and Ellam Inba Mayyam (1981) in a two-year period.
[6] His final directorial Maharasan (1993), had Kamal Haasan in the lead role, who refused to take any salary for the film, in ode to his friendship with Rangarajan.
Following his film career, Rangarajan worked on the television series Raghuvamsam and also made a telefilm for Singaporean producers.
His son, G. N. R. Kumaravelan, apprenticed with Kamal Haasan for films such as Sathi Leelavathi (1995) and Marudhanayagam, and then debuted as a director in the late 2000s.