The romantic comedy is being directed by Kapil Sharma; the son of astronaut Rakesh Sharma, who was the first Indian to travel into space. It goes on floors next month.
It is learnt that Shrishti fell in love with the script and decided to cast John, as she felt it suited his playboy image.
Chitrangada has been cast opposite the Dostana hunk. Talks are on with three others actresses to play the parallel leads.
Hip take on trends
Sharma who makes his debut as a director with this project, has worked as a first assistant on Drona, Being Cyrus and the Hollywood film The Darjeeling Limited.
He says, "More than just being a romcom, it is an urban, hip and cool take on today's trends and culture. I think there can't be anyone better than John who represents that bracket. He not only has international good looks, but is also a Mumbai boy."
About his leading lady, he says, "I find her very sophisticated and gorgeous, but equally in tune with her culture and values.
It's an exciting combination to have these two actors in the same film. Both John and Chitrangada play characters that are extremely real and easy to identify with.
They won't be caricatures that one usually finds in our movies."