The trailer was launched July 25 on small screen as well as internet, and the stupendous response has left director Madhur Bhandarkar extremely happy.
"I am overwhelmed by the great response the promo has got. This is just the beginning," Bhandarkar said in a statement.
Kareena plays Mahi Arora, an actress in the film, which narrates the ups and downs in the life of a movie star.
The trailer captures many facets of an actress' life - the struggle, success and downfall, and Kareena looks smashing in most scenes, including the item number "Halkat jawaani".
"Heroine", produced by UTV Motion Pictures, will release Sep 21.