In his first film, Cheeni Kum (2007) advertising professional-turned-filmmaker R Balki did the improbable: he made Amitabh Bachchan don a chef’s hat for one of his most memorable performances in recent times. After a gap of two years, Balki is again re-creating a fresh character for his favourite performer, senior Bachchan in his upcoming film. In Paa, which releases on December 4, the veteran actor plays a 13-year old kid named Auro, who is diagnosed with Progeria (a condition where a kid ages three times faster than normal).

Eerily similar to the Brad Pitt-starrer The Curious Case Of Benjamin Button, there is a twist in Balki’s version: son Abhishek Bachchan, cast as a politician in the movie, plays senior Bachchan’s father, while Vidya Balan is the dutiful wife.

While there has been enough talk about Bachchan’s amazing five-hour prosthetic work during make-up, Balki, who is also the scriptwriter of the film, is quick to add, “The film is not meant to be an awareness building exercise about Progeria; rather its about the bond between father and son.”

With shooting schedules in London, Malaysia and India, the most challenging task, explains the director, was ensuring that Big B’s larger than life on-screen persona didn’t creep into the film. “I worked hard to prevent his overawing presence from overshadowing the movie,” says Balki.