"He (Ranbir) is usually not in the race where people try to watch him. His highs and lows are different. His rhythm is different. He is a true actor," Ali said.
Ranbir and Ali had previously worked together in the 2011 award-winning film "Rockstar". Comparing the two films, Ali said: "I feel that in this film ('Tamasha'), Ranbir has done a lot more difficult role and a more multi-layered role than 'Rockstar'.
"You can definitely relate to it and you'll feel that this is happening with me. I'm excited for Ranbir's role in the film. And there is a significant anticipation to know what the audience is going to say," he added.
Ranbir will be seen in the film with Deepika Padukone -- with whom he shared a relationship earlier. Talking about casting them, he said: "Whenever you cast for a film, you don't cast two characters simultaneously, but one by one. I never think of pairs. I saw that Ranbir fit the bill for Ved's character and Deepika was suitable for Tara and that's why I cast them separately."
"Tamasha" will hit the theatres on November 27.
