Though Amitabh Bachchan plays a pivotal role of Ashwatthama in Nag Ashwin’s dystopian blockbuster Kalki 2898 AD, the megastar hadn’t watched the complete film until Sunday. In his blog post, Big B revealed that he watched the movie in Mumbai’s IMAX theatre with his son Abhishek Bachchan and his friends. Amitabh finished his weekly meet with fans outside his house, Jalsa, before heading to the theatre. He wrote, “A Sunday of Sundays .. the well wishers at GOJ and then to Kalki with some friends to see on big screen…