You can cite many reasons: Amitabh Bachhan, Dhanush, R Balki, Illiaraja, Films promo looks good, Film looks fresh etc etc….. recently I saw the second trailer: Shamitabh‘s 2nd trailer is mindblowing! The mannerisms of Amitabh Bachchan which Dhanush copied with finesse, the Immortal voice of Amitabh on Dhanush’s face…. and the Dialogue: Ye awaz kisi kutte ke muh se bhi achchi lagegi! simply leave you awestruck!!
The track, reportedly a last minute addition to the film, was recorded in Mumbai. The accompanying video was filmed in Kolkata, at the home of Rabindranath Tagore who wrote the song.