While Gopi is looking for a job, Hari, a harmonium player, aspires to become a music composer in the film industry.

Their neighbour is Prabhu, a college student who spends all his time smoking, painting and singing.

During this time Maha's parents force her to discontinue her tuition as some of their relatives suspect she and Gopi are in a relationship.

Gopi and Hari are evicted from their room for not paying the rent, and seek shelter with Mani, a rickshaw puller.

[5] Ravi was earlier asked to audition for Bharathiraja's Niram Maratha Pookkal (1979) as a dubbing artist for the lead character.

[10] The song "Ithu Oru Pon Malai" was written by Vairamuthu, making his cinematic debut.

[14][15] The rock and roll song "Madai Thiranthu" was later remixed by Yogi B and Natchatra in their album Vallavan.

[16][17] A remix version of "Ithu Oru Pon Malai" is featured on music artist M. Rafi's album Aasaiyae Alaipolae.

[18] Ilaiyaraaja later reused "Dhoorathil Naan Kanda" as "Vennello Godari" for the Telugu film Sitaara (1984).

[19] Nizhalgal was released on 6 November 1980 alongside Varumayin Niram Sivappu with both films having similar themes of unemployment.

[9] Radhakrishnan of Kalki praised the performances of newcomers as natural, Ilaiyaraaja's music and cinematography as colourful and concluded by calling direction as the reality of life as shadow.

[21] Although the film's story, music and the performance of the cast members received critical acclaim, it failed at the box office.

It was one of the two Tamil films to be screened at the festival; the other being Doorathu Idi Muzhakkam which was released the same year.

[25] In 2008, short filmmaker R. V. Ramani in an interview with The Hindu recalled Nizhalgal as being a film that made a strong impact on him.

[26] In a 2015 interview, Bharathiraja noted that he had to return to mainstream filmmaking due to the financial failure of Nizhalgal.