Basking in the success of his latest outing "Once Upon A Time in Mumbaai", Bollywood actor Emraan Hashmi can't stop smiling, but more than that he is raving about his seasoned co-star Ajay Devgn in the movie.

"Ajay is a very chilled out guy and made his co-stars feel very comfortable. He is a very non-interfering person and never interferes in his director's or anybody's work, " Emraan told.

"He is extremely focused and has oodles of intensity on screen. It was a great learning experience working with him...I got to know so much from him, " he added.

The thriller portrays Ajay as an underworld don and Emraan as his protege, who usurps the established order to claim the throne.

Also starring Kangana Ranaut and Prachi Desai, the movie has been directed by Milan Luthria.