Anand (Raghuvaran), from Chennai, joins as an engineer in the Ezhavathupuram Dharmaraja cement factory, owned by J. Kulashekara Perumal (Ramanamurthy). He is appalled by the cruel work environment and bad pay. He becomes friendly with Senthamarai (Deepak), a casual labourer and starts liking Gowri (Rathna), Senthamarai's sister. Their father a freedom fighter Subbiah (Vathiar R.K. Raman) takes loans from the factory manager Arjun to manage the family.
Arjun takes nearly half of the daily wages of the workers as his commission. Ramkumar (Ranga), son of Dharmaraja and nephew of Kulasehakara Perumal is a Director of the company. Anand and Ramkumar were close friends in college. Anand complains about Arjun and Ramkumar reprimands Arjun.
Gown suffers from a pollution-related lung disease but does not inform anyone. Sudhakar, a young casual worker falls sick due to the same lung disease. The Government doctor Prema advises that the disease is in an advanced stage and he must be taken to Chennai for treatment. Kulashekara Perumal refuses treatment and Sudhakar dies. Anand is shocked by the cold indifference of the owner and the management and requests Ramkumar to attend to the factory's pollution issue and demands other benefits for the workers. Both Ramkumar and Kulashekara Perumal refuse his demands and throw him out.
In order to avoid paying compensation to Sudhakar, Ramkumar tries to get a false certificate that Sudhakar was drunk when he died. Doctor Prema who treated Sudhakar refuses it and Ramkumar comes personally to meet the doctor and realizes that she was his ex-lover, whom he ditched. Doctor Prema informs Anand that she had sent a health report to the Health Ministry, but no action has been taken as Ramkumar buys over all the officials. Anand speaks to Ramkumar about this but Ramkumar beats him up. Anand initiates action and forms a Union at the factory and goes on strike.
Meanwhile, Senthamarai gets a job in Dubai and when he leaves the town, Arjun kills him. The new Manager of the factory, Settaya tells Arjun to hide in Chennai and he buries Senthamarai's body in the factory.
Anand realizes that Gown also suffers from lung disease and takes her to Doctor Prema who assures that she will recover soon.
The management refuses the workers' demands and the strike continues. Ramkumar tries to bribe Anand which he refuses. Settaya schemes and gets Anand arrested on a false complaint of a murder attempt on Ramkumar. Using this opportunity, Settaya convinces the workers to withdraw the strike by promising to build a chimney at the cost of Rupees I crore to address the pollution issue. The workers agree to resume work. Subbiah seeks lawyer Balan, a trade union leader for help. Balan convinces the bewildered villagers and bails out Anand. Balan writes a letter to the Government and they decide to send a notice to the factory.
News about Senthamarai's dead body leaks out and Subbiah along with Anand and other workers rush to the factory. At the same time, Settaya and Ramkumar decide to blow up the factory, claim insurance, and construct a new factory. Anand and the workers see the bombs and remove all, except the one kept near the room in which Settaya is hiding. Ramkumar and Kulasekhara Perumal escape but Settaya dies in the bomb blast. Anand and the workers take over the factory and run it with the support of Balan. A new revolution dawns...
[from the book Pride of Tamil Cinema: 1931 to 2013 by G Dhananjayan, Blue Ocean Publishers 2014]