Thunaivan is a 1969 Indian Tamil-language devotional film directed by M. A. Thirumugam and produced by Sandow M. M. A. Chinnappa Thevar. It was written by V. Balamurugan, while the music was composed by K. V. Mahadevan. The film stars Sridevi, A. V. M. Rajan and Sowcar Janaki while Major Sundarrajan, Nagesh, Sachu, Vennira Aadai Nirmala and K. B. Sundarambal are featured in supporting roles. The film marked Sridevi's first leading film role of her career at the age of five, playing Muruga. It was partially filmed in black and white and Eastmancolor, and was a commercial success, running in theatres for over 100 days. The film was remade in Hindi as Maalik.

Plot

Velayudham (A. V. M. Rajan), an orphan and a devotee of Lord Murugan lives in the Murugan Temple of Pooncholai town with the support of the priest Ponnambalam (Senthamarai). The temple trustee (Major Sundararajan) comes for a special Pooja and notices the ruby stone missing in the deity's spear. He blames Velayudham and beats him and threatens to send him out of the town if it is not returned by him the next day. An upset Velayudham pleads with Lord Murugan for justice and since the stone could not be traced, Ponnambalam gives his relative contact in Coimbatore and tells him to leave the town to avoid getting any punishment from the trustee. The next day, Ponnambalam finds the ruby inside the temple and rushes to stop him but it is too late as Velayudham has already left by train. On reaching Coimbatore, he loses his bag containing the address of Ponnambalam's relative. Lost in a new place, he finds solace in a discourse happening there by Kirupananda Variar and believes that Lord Murugan will certainly help him.