The film stars Sivaji Ganesan and Radha, with Vadivukkarasi, newcomers Deepan and Ranjini, Janagaraj, Sathyaraj, Aruna, Veerasami and Ramanathan in supporting roles.

Also living with them is Ponnatha's daughter Rasamma, her husband and Malaichami's orphaned nephew Chellakannu, who assists him at his farm.

She throws a feast for them where she requests they kill Kuyil and promises that she will take care of the consequences by spending money for their case.

She reveals, after making Malaichami promise that he would not proceed to argue on her behalf as it would negate the purpose of her sacrifice, that the person she killed was Mayilvaganam, Rasamma's biological father.

Malaichami is spellbound by her sacrifice and vows that he will not die till Kuyil returns and chooses to stay in her hut.

The story of Muthal Mariyathai was developed by Bharathiraja from two sources: an English-language film about "an old painter and a young girl who is attracted to his paintings.

Gradually, she becomes attracted to the person as well", and a story in Jayakanthan's novel Samoogam Enbadhu Naalu Paer about "the relationship that develops between a young teacher who comes to a place and a local administrator who is in a bad marriage.

[8] According to Selvaraj, the romance between the characters Malaichami and Kuyil was inspired by the manner in which the Russian novelist Fyodor Dostoevsky developed a relationship with his assistant Anna.

[9] Bharathiraja himself produced the film under Manoj Creations, while cinematography was handled by B. Kannan and editing by V. Rajagopal and P. Mohan Raj.

[8] Muthal Mariyathai was Radha's 99th film as an actress; she stated that when Bharathiraja offered her the role of Kuyil, she "took it with both hands".

"[13] This was the feature film debut of Sasha Selvaraj, who was given the stage name Ranjini, and played Sevuli, the daughter of Sengodan (Veerasami).

Ranjini, who was then studying in Singapore, arrived in Madras to take a break from education, and hoped that filming would conclude within two weeks.

[10][12][16] Though Ganesan was known mainly for his melodramatic performances and powerful dialogue delivery, Bharathiraja asked him to tone them down for playing Malaichami and "just be himself".

[17][18] At Bharathiraja's request, Ganesan acted without a wig or makeup, and wore only a dhoti and shirt while filming his scenes.

[23] Writing for The News Minute, Nandhu Sundaram said that in the film, "society is a throbbing entity that is alive in every sense of the word, and sometimes it is malignant as well.

[6] Writing for The Times of India, Deepauk Murugesan notes that Bharathiraja used the relationships in the film "as a commentary on caste and its subliminal presence in our interactions".

[25][26] Neither liked the film after viewing its rough cut because they felt it "wasn't youthful", but Bharathiraja insisted that Ilaiyaraaja compose the score.

[31] The tune of "Antha Nilava Thaan" was later used by Ilaiyaraaja in "Mujhe Bahon Mein Bhar" from the 1989 Hindi film Mahaadev.

[17] Ananda Vikatan said that when detractors were talking about the end of Ganesan's era in Tamil cinema, Bharathiraja proved through an intense script and character that his saga was not over yet.

[34] Though Vadivukkarasi received acclaim from critics for her performance, she was the subject of vitriol from fans of Ganesan due to her character's antagonistic nature.

[23] Muthal Mariyathai is included alongside other Ganesan-starring films in the compilation DVD 8th Ulaga Adhisayam Sivaji.

[45][46] In a comedy scene from Thalattu Ketkuthamma, a man (Goundamani) sings "Poongatru Thirumbuma" to impress his wife (Vijay Chandrika), and his nephew Rasaiya (Prabhu) completes the lyrics after the former has forgotten them.