Ramachandran began the 1970s with roles in such social dramas as "Maattukara Velan" and "Engal Thangam" (both released in 1970), both of which enjoyed commercial success. The following year, he received the National Film Award for Best Actor for his role as a cycle rickshaw driver in "Rickshawkaran", making it the first film and him the first actor from South Indian cinema to win the award. It went on to become the highest-grossing film of the year. He then directed and produced the action-adventure film "Ulagam Sutrum Valiban" (1973) where he also starred in dual roles as brothers, a scientist and a CBI officer. It became his most commercially successful film to that point. Ramachandran retired from filmmaking in 1978 to take up his duties as the Chief Minister of Tamil Nadu; his last venture, entitled "Madhuraiyai Meetta Sundharapandiyan," was a commercial failure.