Actresses consumed by their internal politics make it very difficult for a director to sign more than one for a particular film, says director Zoya Akhtar, but she is happy to have Kalki Koechlin with Katrina Kaif in her forthcoming film "Zindagi Na Milegi Dobara".

"You have to understand that in the Hindi film industry it's very difficult to star two actresses in a particular film. Like Katrina is in the movie and she is a superstar, then a lot of superstars you want to approach won't agree to do the kind of role Kalki did in the film. There is too much politics," Zoya told.

However, she has high regard for Kalki's acting capabilities and feels the Indian actress of French descent fitted the bill for the character she conceived.

"Kalki is a very interesting actress. She is very edgy. Kalki had no such notion. She doesn't come from that school. She's a wonderful actress. I met her through Anurag (Kashyap). I saw her in 'Dev D' and also the yet unreleased 'The Girl in Yellow Boots' and she is superb in it."

Kalki is married to Kashyap.

"She has got a very different role. She is not the heroine of the film. She has that sense of comedy and not over the top. I needed that balance in an actress who could pull that off. I needed someone with that sensibility and Kalki was perfect," said Zoya.

"Zindagi Na Milegi Dobara" is a film on a road trip, which shows how the life of three men, Abhay Deol, Farhan Akhtar and Hrithik Roshan, changes when they go for a holiday. It is set to hit the theatres July 15.

Casting this unusual mix of lead actors was intentional as the audience has an absolutely independent image of each of them, and the curiosity on how they gel in the film would make it more interesting, believes the director.

"When you cast actors who usually don't come together or have a different image in audience's mind, there is a new dynamic, there is a new energy. The inquisitiveness of the audience makes a film more interesting," she added.