After Cheeni Kum, starring Amitabh Bachchan and Tabu, director R Balkrishnan will direct Bachchan once again in Pa. They will be joined by Abhishek and Jaya Bachchan.
The latest actor to join the cast is Vidya Balan.
The actress, who recently signed the dotted line, will play Abhishek's sweetheart. Tabu was earlier considered for the role but the makers felt that she would not suit the role.
While Amitabh has shared the silver screen with his son quite a few times, Jaya has starred with Abhishek only a couple of times before in the 2002 Bengali film, Desh, and Yash Chopra's Laaga Chunari Mein Daag, last year.
Pa will go on floors next year, and is expected to release mid-2009.