Dhanush's Telugu-Tamil bilingual 'SIR' is going to hit the screens in both languages simultaneously. Sithara Entertainments and Fortune Four Cinemas today released the first song from the movie. Titled 'Mastaaru Mastaaru', the lively number has been sung by Shweta Mohan.

Written by Ramajogayya Sastry and choreographed by Sekhar Master, the song brings out the level of adoration that the heroine (Samyuktha Menon) has for a lecturer named Bala Gangadhar Tilak (Dhanush).

GV Prakash Kumar's composition is appealing. Lyricist Sastry said that he kept in mind the tastes of the Telugu audience while writing the song. 'Mastaaru Mastaaru' was written before the Tamil version. The song takes listeners through the romance angle between the leads in the story," he added. The lyricist is also happy that the song provides the perspective of a woman neck-deep in love with an idealistic character. Terming the song an upbeat melody, he adds that it has got an underplayed folk element that has all the makings of a chartbuster.

Co-starring Malayalam star Samyuktha Menon, Sai Kumar, Tanikella Bharani, Samuthirakani, Thotapalli Madhu, Narra Sreenu, Pammi Sai, Hyper Adhi and others, the film has production design by Avinash Kolla.