"He (Naseeruddin Shah) is very calm and reserved, but he gives suggestions, which is very nice," Sunny said in an interview.
"He is a lot of fun to work with. He is not really conversant, but when he gets onto laughing, it's the best feeling," she added.
In "Jackpot", being helmed by "Boom"-fame director Kaizad Gustad, Sunny is paired with Sachiin Joshi and plays Naseeruddin's secretary in the film. Currently, the film's team is shooting in Goa.
The actress, who made her debut with 2012 film "Jism", holds Naseeruddin, 63, in high regard.
She feels honoured to be in the same frame with the actor, who has delivered notable performances in films like "Nishant", "Manthan", "Sparsh", "Aakrosh", "Masoom" and "A Wednesday" throughout his career.
Recalling her first shot with Naseeruddin, Sunny said: "I said to him, 'If you have any advice for me whether it is good or bad, I will take it.' Even if he tells me, 'You were horrible in the shot and you should try like this', I will not get offended."
"Jackpot" marks the Bollywood debut of Tamil actor Bharat.