The film's development began when Ratnam wrote a short story, "Divya", while he was making his first film (1983's Pallavi Anu Pallavi). As the script developed, he renamed it. Ratnam did not plan to film the story until he had finished writing it, and could not begin production until the release of his fourth film (1985's Idaya Kovil). Mouna Ragam was the first film produced by Venkateswaran's Sujatha Films (later renamed GV Films), and was filmed primarily in Chennai, with additional filming in Delhi and Agra. The soundtrack album and background score were composed by Ilaiyaraaja, with lyrics by Vaali. P. C. Sreeram was the film's cinematographer, and its art director was Thotta Tharani. It was edited by B. Lenin and V. T. Vijayan.
Divya is a free-spirited college student from a conservative family whose strict father, Chandramouli, works for the government. She learns that her parents are eagerly awaiting a marriage proposal for her. Unwilling to get married, and hoping that the groom's family will reject her, she deliberately arrives home late to find Chandrakumar (the groom) and his family patiently waiting for her. She talks arrogantly to Chandrakumar to make him dislike her but, undeterred, he says that he likes her and agrees to the marriage. Divya initially refuses, but when her father has a heart attack her family begs her to accept the proposal to aid his recovery. Succumbing to the pressure, Divya marries Chandrakumar.
After their marriage Chandrakumar takes Divya to Delhi, but she cannot accept him as her husband and ignores him. When he asks her what she would like as a wedding gift, she asks him for a divorce. Startled, Chandrakumar asks her why; in a flashback, Divya remembers when she was in love with Manohar, whom she met as a college student. Manohar and his gang assault and rob the son of Thamizhmani, an MP. Divya reports Manohar to the police, and he is arrested. She later learns that Thamizhmani's son had run over a girl with his car, and Manohar stole the money to pay for the girl's medical treatment. Divya feels guilty, and bails him out.
Manohar falls in love with Divya, and tries to win her love; although she initially rejects him, eventually she returns his feelings. Manohar is a member of a revolutionary group who plan to hold an illegal rally. Divya does not approve, and asks him not to attend; he agrees if she will marry him. On their wedding day, Manohar is falsely accused of participating in the rally and arrested. He escapes, and runs to the marriage registrar's office where Divya is waiting for him. A policeman accidentally shoots him, and he dies in front of Divya.
Although Chandrakumar is ready to forget Divya's past, she cannot accept another man in her life. They consult a lawyer who tells them that according to the Hindu Marriage Act of 1955, since they are newly married they must wait one year to file for divorce and they must live with each other for a year.
Chandrakumar is attacked by his company's labourers because he had suspended their union leader. Divya brings him to a nearby hospital, where he survives after receiving treatment. After he is discharged from the hospital, Divya takes care of him and realises that she has fallen in love with him. She tries to show it by wearing the anklets Chandrakumar gave her shortly after their marriage but, irritated by what he sees as Divya's immaturity, Chandrakumar asks her to return to her parents home and books her trip. At the railway station, Chandrakumar gives Divya the divorce papers that she had requested as a wedding gift. Divya breaks down, telling Chandrakumar that she loves him, and they reconcile.
When the last schedule for Mani Ratnam's first film (1983's Pallavi Anu Pallavi) was extended to a year he began work on a story entitled "Divya"—which eventually became Mouna Ragam, his fifth film. According to Ratnam, he began "Divya" as a short story about a couple's wedding night. Although he did not originally plan to film it, after writing the story he realised that it had cinematic possibilities. Ratnam took a one-month break between Pallavi Anu Pallavi shooting schedules, and wrote the script for Divya. He said that Mouna Ragam's script took five years to write.
The film's title came from the song "Naan Paadum Mouna Ragam", from Ratnam's Idaya Kovil (1985). Although he began work on the script while making Pallavi Anu Pallavi, Mouna Ragam did not begin production until after Idaya Kovil's release. Ratnam said that due to budgetary constraints it would have been easier to send the female lead to Bangalore instead of Delhi, but he did not want her to be able to easily return to her parents because she could not adjust to her husband. The line "Neenga thottaa kambilipoochi oorraa madhri irukku", spoken by Divya to Chandrakumar, expressed how she would feel on her wedding night.
Mouna Ragam was Ratnam's first collaboration with cinematographer P. C. Sreeram. He initially narrated the script of Mouna Ragam (when it was titled Divya) to Malayalam film producer N. G. John, but the latter wanted a political film, which eventually became the Malayalam-language film Unaru (1984), also directed by Ratnam. He then pitched Divya to G. Thyagarajan of Sathya Jyothi Films, but Thyagarajan wanted an action film. Mouna Ragam was instead produced by Ratnam's brother, G. Venkateswaran, under his Sujatha Films banner (later renamed GV Films). It was the company's first film production; until then, it had been involved in distribution and finance. The film was edited by B. Lenin and V. T. Vijayan, with art direction by Thota Tharani.
Ratnam cast Mohan, with whom he had worked in Idaya Kovil, as the male lead. Revathi, the female lead, had collaborated with Ratnam on Pagal Nilavu (1984). Ratnam initially had "someone like Anant Nag and Supriya Pathak" in mind when he finished writing Mouna Ragam. Between finishing the story and making the film, he decided to include Revathi, whose performance in Mann Vasanai (1983) impressed him. Nadhiya was also considered for the role, but she declined due to prior commitments. Ra. Sankaran was cast as Divya's father, Chandramouli, Kanchana as the lawyer and V. K. Ramasamy as Chandrakumar's boss. Vani plays Divya's mother and Bhaskar her brother; Kalaiselvi and Sonia play her sisters. Prabhu Deva, who became a successful Indian cinematic choreographer, made his acting debut in the film with an appearance in "Panivizhum Iravu" as a boy playing a flute.
According to Ratnam, the only difference between Divya and Mouna Ragam was the scene with Karthik (which was not part of the earlier screenplay). Divya, the story of a young woman settling into an arranged marriage, did not explore her life before the marriage. Ratnam realised that the story needed to satisfy a wider audience, and decided to give them something that would make them accept the character without questioning Divya's actions. The story dealt with an arranged marriage — two strangers suddenly thrown together — and how they adjust. Ratnam originally resisted this, but reconsidered because its suddenness provided a clear rationale for the Divya's resistance to the arranged marriage. Karthik said he was a "last-minute addition" to the cast; his scenes were shot in a week, and his role was "but a cameo".
Filming began at P. C. Sreeram's house in Alwarpet. Although the film was primarily set indoors in Delhi, Ratnam and Sreeram wanted the indoor scenes to look as lively as those shot outdoors. Since the cast was relatively small, Ratnam did not want it to resemble a play and used backlighting for the interior scenes. Thotta Tharani found a house in the residential area of Kilpauk in Madras (now Chennai) which admitted a great deal of sunlight, making it similar to houses in Delhi. Mouna Ragam was Ratnam's first film to make extensive use of staccato dialogue; this became his trademark style in later films. To reduce production costs, food for the film's crew was cooked at Venkateswaran's home.
While filming the introductory scene of Karthik's character, Manohar, Sreeram had to lie on a bed sheet to film. The crew pulled the sheet, with Sreeram and the camera. Sreeram made extensive use of frontal and profile close-ups, set against long shots with out-of-focus foregrounds. The scene where Manohar plays a prank on Divya's father at a coffee shop, which later became known as the "Mr. Chandramouli scene", was shot in Nungambakkam. Filming was also done at Madras' Presidency College, the Schmidt Memorial on Edward Elliot's Beach and at the Madras Literary Society. While filming the "Oho Megam Vandhadho" scene with Divya dancing in the rain, Revathi tied a handkerchief around her wrist to cover her watch because she felt that Divya would actually do that.
The crew filmed in Delhi for two days, and the scenes set in Agra were shot in one day. Portions of "Panivizhum Iravu" were shot at the Taj Mahal and Madras, and those from "Mandram Vandha" were shot at the India Gate. The scenes involving Karthik were the last parts of the principal photography. In post-production, Mohan's voice was dubbed by S. N. Surendar. The film's final length was 3,987.50 metres (13,082.3 ft).
Mouna Ragam provides insight into the issues faced by married couples, exploring the plight and perception of divorce and how societies need to view the desires of women. Film critic Baradwaj Rangan compared the film to J. Mahendran's Nenjathai Killathe (1980), another story of a woman torn between the man she loves and the man she marries, Antha Ezhu Naatkal (1981) and its Hindi remake, Woh Saat Din (1983). Rakesh Mehar of The News Minute noted that one thing differentiating Mouna Ragam from Antha Ezhu Naatkal and similar films is that it remains focused on Divya. Kumuthan Maderya, writing for PopMatters, described Mouna Ragam a "chick flick", because like other chick flicks, the film allowed romance to blossom between Divya and Chandrakumar, rather than let divorce split them; according to him, "chick flicks center on the romantic worldview of females while gratifying their hopes and dreams usually through a warm and fuzzy denouement".
Manohar was part of a group involved in anti-government activities. Rangan drew similarities between his motives and those of characters in the Italian film The Night of the Shooting Stars (1982) and Unaru. Mouna Ragam's introductory credits feature photographs of Revathi from her childhood through her teenage years which, according to rapper Blaaze, help viewers "understand the girl, the character, her nature". According to Rangan, the scene where Divya is looking after Chandrakumar at the hospital reflects her traditional qualities; with her strengths, she is humane and vulnerable. Divya's mischievous nature is shown in a scene where she teaches a Sardar offensive Tamil phrases, which he says to V. K. Ramasamy's character. Revathi compared herself to Divya, saying that Divya believes in "living life to the fullest" and she was once like that. Sujatha Narayanan, writing for The New Indian Express, described Chandrakumar as a "patient-understanding-and-poised-at-all-times" man and Manohar as a "dashing, brave and epitome-of-the-word-'dude'". Narayanan noted that Divya, like the female leads in most of Ratnam's films, is "practical with strong convictions" and the characters "go through their confusions unapologetically".
According to Rangan, Mouna Ragam's background score was found by critics to suit its scenes and themes. According to Martin Clayton, Trevor Herbert and Richard Middleton's 2003 book, The Cultural Study of Music: A Critical Introduction, "Oho Megam Vandhadho" resembled Broadway and MTV styles of singing and dancing, and the main songs combine American music with Indian vocals by S. Janaki. Sangeetha Devi Dundoo of The Hindu considered that Ratnam used rain in the film to accentuate the "childlike, free-spirited nature" of Divya. The sarangi and nadaswaram (South Asian instruments) are used in the music accompanying Chandrakumar and Divya's wedding. In scenes of the couple sightseeing in Delhi, light synth-based music depicts them as modern tourists in their own country. The restaurant scene with Manohar and Divya includes awkwardly played sitar music, indicating the couple's emotions. Spanish music is used for the fight scene when Manohar attacks the MP's son.
The theme of a heroine moving to a strange place where she does not know the local language is replicated in Ratnam's later films, Roja (1992) and Bombay (1995). The heroine has a dilemma; because she does not know the language in Delhi she can barely socialise with local people, and she is at loggerheads with the only person with whom she can relate. According to Rangan, the restaurant scene with Manohar and Divya is the first instance in Tamil cinema where a man invites a woman for a cup of coffee. He compared it to Oru Thalai Ragam (1980), in which the protagonists barely spoke. Ratnam said that he was inspired by the Doors and the Beatles and, although it was not uncommon to invite a woman for a cup of coffee, it was not reflected in the Tamil cinema of the time.
Mouna Ragam's soundtrack album consists of five songs composed by Ilaiyaraaja with lyrics by Vaali, sung by S. Janaki and S. P. Balasubrahmanyam. It was released by the Echo Audio Company. According to The Cultural Study of Music: A Critical Introduction, "Oho Megam Vandhadho" (featuring Divya dancing with several teenage girls) is a reworking of Gene Kelly's "Singin' in the Rain". "Nilaavae Vaa" is the second song on both sides of the soundtrack's original LP record. "Mandram Vandha" is based on the Keeravani raga, with Natabhairavi elements. It was later adapted by Ilaiyaraaja and used twice in the 2007 Hindi film, Cheeni Kum: as the film's title track and the melancholy "Sooni Sooni". The composerr K said that the theme music he composed for Yuddham Sei (2011) had a "tinge" of Mouna Ragam.
The soundtrack received positive critical reviews. Filmmaker Poongkothai Chandrahasan praised "Nilaave Vaa"'s cinematography and said, "Ilaiyaraja's music is such that even when you listen to it ten years later, you still remember the song". Actress Kushboo called "Chinna Chinna Vanna Kuyil" an "unforgettable song", adding: "My Valentine's Day is incomplete without listening to it at least once". Nandini Ramnath wrote for Mint, "Bombay's director, Mani Ratnam, can't make a movie without including a shower from the heavens or a splash in some kind of water body. His best rain song is 'Oho Megham Vanthatho'". Srinivasa Ramanujam of The Hindu also praised the song.
S. Saraswathi of Rediff called "Nilaave Vaa" a "timeless classic that you never tire of". Sruthi Radhakrishnan of The Hindu described "Mandram Vandha" as a "song that drives fans crazy", and "Chinna Chinna Vanna Kuyil" "showcased Janaki's vocals with such astounding effect". About "Panivizhum Iravu", she said: "It's one of those only-80s songs that served as a stand-in for sexual tension, where you'd have two people looking intensely at each other. And it's a brilliant composition too. The percussion gets you hooked and the chorus is almost eerie." For Firstpost, Apoorva Sripathi said: "The film traces a couple's marital discord — the heroine is torn between the man she loved and the man she finally marries — and the soundtrack beautifully mimics it." She called "Mandram Vandha" a "masterpiece, sung soulfully by SP Balasubramaniam." Sify praised the songs, the background music and the re-recording, calling Ilaiyaraaja the "king of re-recording".
Mouna Ragam was publicised with a shot of Revathi clinging to a lamp post and singing, which Ratnam confirmed as being inspired by "Singin' in the Rain". Before the film's release, a Central Board of Film Certification member wanted it to receive an "A" (adults-only) certificate because the female lead asks for a divorce; after much deliberation, it received a "U" certificate. Mouna Ragam was released on 15 August 1986, India's Independence Day. Despite opening to modest audiences, it picked up and became a box-office success; Ratnam considered Mouna Ragam his first commercial success. The film was later dubbed in Telugu and released with the same title, which was also a success.
Mouna Ragam was screened at the 11th International Film Festival of India, the only Tamil entry. It has also been screened at other film festivals, including Mani Ratnam's Love Films at London's National Film Theatre in 2002, a Retrospective of Mani Ratnam's Films at the 2002 Calcutta Film Festival and at the 2002 Locarno Film Festival. An enhanced 5.1 Digital Dolby soundtrack was released in May 2008 by Bayshore Records.
The film was critically acclaimed. In a 31 August 1986 review, the Tamil magazine Ananda Vikatan praised Revathi and Mohan's performances and the film's camera work, music and lack of masala, giving Mouna Ragam a score of 43 out of 100. Kaviya Shetty of India Today wrote in 1994, "[Mouna Ragam] found the perfect formula of a strong storyline and great music, presented in a fresh visual style that caught the audience by surprise". According to Karan Bali of Upperstall.com, "Mouna Ragam is looked at as Mani Ratnam's breakthrough film and though somewhat dated in places in terms of both content and style, the film has some of his finest moments". He criticised the film's "smaller comedy tracks", saying that they "don't really add anything to the film"; although he called the film "too simplistic", Bali concluded that it "is well, well worth a watch even today".
In 2000, Gautaman Bhaskaran called Mouna Ragam "simple and shorn of pretensions" in The Hindu; a decade later, he praised the film's realistic portrayal of urban Tamil people. Pavithra Srinivasan of Rediff said, "It took a Mani Ratnam to move away from cliched romantic dialogues and capture subtle nuances that add so much richness to the story, introduce proper, three dimensional characters that lived breathed and sorrowed like everyone else".
At the 34th National Film Awards, Mouna Ragam received the National Film Award for Best Feature Film in Tamil. Ratnam received the Award for Best Tamil Director at the 36th Filmfare Awards South.
Mouna Ragam is a milestone of Tamil cinema and Mani Ratnam's breakthrough film. The first love story set outside Tamil Nadu, it has been acclaimed for combining box-office success with elements of an art film.
The film introduced techniques such as soft-focus shots, flare filters and backlighting, which became popular in Tamil cinema. Ratnam continued using these techniques in his later films, notably Nayakan (1987) and Agni Natchathiram (1988). Mouna Ragam catapulted Karthik to stardom despite his cameo appearance, and his "Mr. Chandramouli" dialogue became popular. Mouna Ragam was remade in Hindi as Kasak in 1992, starring Rishi Kapoor and Neelam Kothari.
According to a Rediff.com article, "The Most Memorable Mani Movies", "This was arguably the film that announced Mani Ratnam to the Tamil film industry as a talent to watch out for. An excellent script by Ratnam himself, [cinematography by P. C. Sreeram] and a lilting score by [Ilaiyaraaja] made it a hit with both critics and moviegoers". Deccan Chronicle listed Karthik and Revathi on its "Top 10 Jodis" of Tamil cinema; they "made a fresh pair and were adored by the youth, especially the college students. Their awesome on-screen chemistry in Mouna Ragam was a talking point back then". For the April 2013 centenary of Indian cinema, Forbes India included Revathi's performance in its 25 Greatest Acting Performances of Indian Cinema. Mouna Ragam was included in a CNN-News18 poll of the most popular romantic films of all time, and Sify included the film on its list of top five Ilaiyaraaja-Ratnam films.
Art director Sabu Cyril ranked Mouna Ragam fourth on his list of India's best films, praising its story, narration and screenplay. Poongkothai Chandrahasan told The Hindu, "Mani Ratnam had the guts to make a film that interesting with a different storyline. Also the way P. C. Sriram shot the film was so beautiful". Kushboo called Mouna Ragam her favourite "film with a strong woman character." Mouna Ragam is the name of a Tamil orchestra also known as Murali's Mouna Ragam.
A scene in Mouna Ragam when Manohar tries to declare his love for Divya through the college intercom (in response to her challenge) was parodied in Thamizh Padam (2010), with Shiva and Disha Pandey. A Telugu film, also entitled Mouna Ragam, was released in 2010 but was unconnected to Ratnam's film. Rangan compared Mouna Ragam to the Hindi film Hum Dil De Chuke Sanam (1999); in both films "the disengaged wife was tempted, at several points, to snap free of matrimony, but what held her back, eventually, was the innate decency of the man she married". Vallamai Tharayo (2008) was compared by critics to Mouna Ragam because it also features a woman (Chaya Singh) reluctantly married to a man (R. Parthiepan) whom she does not love; Pavithra Srinivasan of Rediff.com called it "a dull reworking" of Mouna Ragam. Neelima Menon of The New Indian Express called Yathrakarude Sradhakku (2002) a "watered-down version" of Mouna Ragam. Singer Krish said that his acting debut Puriyadha Anandam Puthithaga Arambam (2015) was a line from "Chinna Chinna Vanna Kuyil". Actress Sri Divya called Revathi's character her "all-time favorite role", saying that she played a similar role in Mallela Theeram Lo Sirimalle Puvvu (2013). Actor Karthi said that his character in Naan Mahaan Alla (2010) was similar to Karthik's "moody yet jovial" character in Mouna Ragam. Writing for Mint, Nandini Ramnath compared Tanu Weds Manu (2011) to Mouna Ragam because of the similar relationship between their male and female leads. Footage from Mouna Ragam was used in Romeo Juliet (2015). The Hindu's S. Shiva Kumar wrote in his review of Rab Ne Bana Di Jodi (2008), "A carefree and cheerful girl whose boyfriend dies on the day of the wedding is forced to marry a staid suitor by the father who suffers a heart attack. The similarity [with Mouna Ragam] ends there."
Raja Rani (2013) was compared to Mouna Ragam, sharing the theme of marital problems; in the former film, the male (Arya) and female (Nayanthara) lead characters both have past lovers. The restaurant scene with Manohar and Divya was recreated by Prasanna and Lekha Washington in Kalyana Samayal Saadham (2013). Vaibhav Reddy compared his character in Kappal (2014) to Manohar in Mouna Ragam because of their shared effervescence. In one scene, which Reddy compared to the "Mr. Chandramouli" scene, his character pesters the heroine to fall in love with him. M. Suganth of The Times of India called the Malayalam film Bangalore Days (2014) a "sort-of Mouna Ragam with the roles reversed", since it was about a man who is unable to forget his past love and accept his wife. The "Mr. Chandramouli" scene was reenacted in Idhu Enna Maayam (2015). Malini Mannath of The New Indian Express compared Maalai Naerathu Mayakkam (2016), written by Selvaraghavan, to Mouna Ragam because its female lead is unhappily married to the male lead; Baradwaj Rangan called the film "Mouna Raagam, Selvaraghavan style". Director B. V. Nandini Reddy said that the story of a bride unhappy with her husband in Mouna Ragam inspired her to make Kalyana Vaibhogame (2016), where neither the bride nor the bridegroom is interested in marriage.