A Temple in the Heart) is a 1962 Indian Tamil-language romantic drama film directed, produced and written by C. V. Sridhar.

The film stars Kalyan Kumar, Devika and R. Muthuraman while Nagesh, Manorama and Kutty Padmini play supporting roles.

The original soundtrack album and background score were composed by Viswanathan–Ramamoorthy, while the lyrics for the songs were written by Kannadasan.

The remainder of the film shows how Murali sacrifices his love for the sake of the couple's happiness and cures Venu.

Sridhar remade the film in Hindi as Dil Ek Mandir (1963) and in Telugu as Manase Mandiram (1966).

Devastated upon hearing the news, Murali swears a vow of lifelong celibacy and devotes himself to save people suffering from cancer.

Venu requests Murali to marry Seetha in case the operation is unsuccessful as he does not wish for his wife to become a widow.

However, when Murali reads the results of the operation, he becomes so thrilled at its success that he unexpectedly dies of high blood pressure due to his over-excitement.

Woven into the story is a subplot following a girl, who is in the same hospital Murali works in and undergoes treatment for the same disease that Venu contracted.

[18] S. Rama Rao was originally supposed to play that role, but lost it due to arriving late on the first day of shoot.

While film historian Randor Guy and K. S. Sivakumaran of Daily News Sri Lanka state that the film was completed in four weeks,[26][27] Ramya Kannan of The Hindu, and Tamil Canadian journalist D. B. S. Jeyaraj state the completion time to be 22 and 28 days respectively.

[32] The original soundtrack album and background score for Nenjil Or Aalayam were composed by Viswanathan–Ramamoorthy (a duo consisting of M. S. Viswanathan and T. K. Ramamoorthy), while the lyrics were written by Kannadasan.

[34] The inspiration for the opening line of the song "Engirundhalum Vaazhga" came to Kannadasan when he happened to hear the speech of C. N. Annadurai, the then Chief Minister of Tamil Nadu, on actor Sivaji Ganesan at a film function.

[39][40] Lakshmi Palecanda, writing for the magazine Khabar, considered that the song reflects "accusation, sorrow, and disillusionment.

[44] Film critic Baradwaj Rangan, writing for The New Indian Express, opined that "Engirundhaalum Vaazhga" had set "the precedent for several generations of jilted lovers".

"[29] Following Viswanathan's death in July 2015, the news agency Press Trust of India wrote that "Ninaipadhellam" was "memorable for the deep sense of solace it offered to wounded hearts.

"[46] Anand Venkateswaran of The Wire noted, "MSV's style is less about making words sit in a meter than about a musical empathy with the meaning.

"[47] A critic from Dina Thanthi noted Kannadasan had an uncanny ability to deliver perfect situational songs and cited "Sonnathu Neethaana" as an example.

The reviewer praised the performances of Devika and Kalyan Kumar, and noted that though there were clichés, "the presentation is racy and superb.

[60] Sridhar remade Nenjil Or Aalayam in Hindi as Dil Ek Mandir (1963) and in Telugu as Manase Mandiram (1966).

[3][62] California-based Indian filmmaker Jag Mundhra was keen on remaking Dil Ek Mandir in English and Hindi, effecting some marginal changes in the film treatment.

Nenjil Or Aalayam attained cult status in Tamil cinema and became a trendsetter for fast-paced filmmaking and triangular love stories.

[66] In 2004, Baradwaj Rangan wrote "A Then Nilavu or a Nenjil Or Aalayam or a Kaadhalikka Neramillai, Sridhar films all, in those days was considered the work of a genius with form.