Bharath (Rajinikanth) is a young, educated man, unaware on the whereabouts of his father. Shanti, (Sharada) his mother tells him the past about his father, but, on her deathbed.

Flashback: A young Gopinath (Sathyaraj), educated and a rich man, arrives Paapampatti village (where then-young Shanti resides), for engineering a construction project. Over time, he slowly gains her interest, for her being an innocent village girl she was, working under him as a manual labour under his unit, emulating innocence. Smitten, she, in turn, entrusts him, wherein he takes the fullest advantage over her. Soon after the construction work Gopinath was engineering for, got over, he goes about to move out of the village. Getting to know his departure, Shanti runs into him. Gopinath justifies her that he would return soon to take over her arms lawfully in front of the society and it convinces Shanti as she waved him off. Weeks passed, Shanti, who eagerly and desperately awaited for Gopinath to return expecting the promise he lent, be fulfilled, hears from fellow villagers that he was about to get wed to another rich woman. Shocked, she travels to Madras with the help of the visiting card that Gopinath had given her earlier to meet him. After both having a furious heads-up, Gopinath, who not only displayed his original ill-natured attire but expressed a denial too — indicating the difference in their stature, to accept her. Also stating she had no proof regarding intimacy that made her conceive, berates her a 'gold-digger'. Become aware of the innocence as a cloak that he used for exploiting her, which he himself admits at the end, exasperates her. Insulted Shanti swore him that one day her child will question him on the future of his vile actions and make him forcibly confess the truth about his depraved activity in front of the whole society and leaves. Over the course of time, Shanti faces hardships and raises her son to be what he becomes as now not revealing her past until her final hour.

Back to the Present, She makes Bharath promise to fulfil her challenge before passing off. Bharath, anguished having lost his mother, takes up her vow as a challenge of making his biological father confess the truth within next year 31 August, the day he lost his mother, at her first remembrance.

Bharath leaves for the city and meets his biological father, Gopinath, as some strange man not revealing his true, real identity. After a business dealing, Bharath uses a brilliant, yet criminal strategy, to extricate money out of Gopinath which he uses as an investment to start his own business by venturing into the construction sector and rises to No 2 company within months keeping Gopinath's construction company, 'Gopinath constructions', which was the No.1 company in the same field, as his target. This angers Gopinath, as a result of which, Gopinath views Bharath as a strategic business enemy. Both Bharath and Gopinath try to overtake each other in an illegitimate way. Bharath however, hardworking and brilliant, also with the help of Sanjeevi (Goundamani), his local trustee, out cuts all chances and goes to make his company outrank Gopinath constructions to No.2 thus, becoming No 1.

Later Bharath once helps a girl from goons and takes to her home only to find out that the girl is Pushpa, Gopinath's daughter who happens to be his step-sister. Due to this, Bharath wins the affection of Mrs.Gopinath (Who happens to be Bharath's stepmother) who starts to treat her like her own son, similar to Pushpa's brother. Bharath tactically arranges for a marriage of Pushpa with the son of a wealthy man Kumeresa Gounder on 31 August, the first remembrance of his mother. Kumaresa Goundar fully is made aware of Bharath's swearing, so he too helps him to fulfil the challenge which he has against Gopinath. Bharath also uses the love connection between his rich born step-brother and austere Sanjeevi's sister to corner status-minded Gopinath by arranging the marriage on the same 31 August. Bharath uses every possible way to torture Gopinath to make him realise his mistake but Gopinath does not reciprocate instead becomes angrier as things go beyond business to personal vengeance. Bharath tactically makes various bottlenecks for Gopinath on Aug-31st, as Gopinath comes to realise that there is more than business Bharath was taking this plight into.

Having lost his clutch with business, wealth and status, Gopinath slowly goes into bankruptcy thus unable to afford to his own children' wedding. In the meanwhile, Bharath invites him to inaugurate his orphanage on 31 August, the date when he planned to fulfil his mother's wish. Gopinath, furious with Bharath since he is the reason for his slump, hires a local goon Michael (Raghuvaran) who once was his enemy (also Bharath's) and proposes to kill Bharath at his own inaugural function on the same 31 August. Bharath reveals his mother's identity in the function as he waits for Gopinath to accept his mistake.

Does Gopinath recognise who Bharath is and whether he accepts him as his son frames the end of the story.

• Rajinikanth as Bharath
• Sathyaraj as Gopinath
• Ambika as Uma
• Saharada as Shanti
• Goundamani as Sanjeevi
• S. Ve. Shekhar as Ashok
• Raghuvaran as Michael
• Visu as Kumerasa Gounder
• Deepan
• Viji as Ponni
• Vadivukkarasi as Gopinath's wife
• Jothichandra as Pushpa
• Delhi Ganesh as construction contractor

Sathyaraj acted as Rajinikanth's father in the film though he was in fact 4 years younger to Rajinikanth.

The music was composed by Ilaiyaraaja. The track "Ennama Kannu" was later remixed in the film Thiruvilayadal Arambam (2006).^[6] The song inspired a 2000 film of same name also starring Sathyaraj.^[7]

Mr Bharath got terrific openings at the box office. The film was appreciated for Rajini's style of tackling Sathyaraj but the critics gave it a thumbs down for tampering the original script of Trishul and miscasting of Sathyaraj and S. Ve. Sekar in the roles of Sanjeev Kumar and Shashi Kapoor. Rajini's stardom saved the film from becoming flop to making it a 100-day run in few centres.^[8]