"He was there full-on rehearsing, forgetting the culture of the kinds of films he has been doing. He has totally changed and rediscovered himself in this kind of filmmaking.
But the fact is that in this film you will, for the first time, see that Emraan Hashmi is a stellar comic actor," the 42-year-old said here Thursday at a special screening of the film.
"Nobody has ever found this funny bone in Emraan and I am so proud that he did it for our film," he added.
"Shanghai" also stars Abhay Deol and Kalki Koechlin and hits theatres June 8.