Ranbir Kapoor is joining hands with his good friend and filmmaker Ayan Mukerji for a superhero flick titled ‘Brahmastra’. Mouni Roy, who became popular with her ‘Naagin’ act on the small screen, is roped in to play an important role and buzz suggests that the actress will be playing a deadly vamp opposite Ranbir. ‘Brahmastra’ is the first film in a three-part fantasy adventure produced by Karan Johar. Ranbir will share the screen space with Alia Bhatt for the first time and the film also stars Amitabh Bachchan in a pivotal role. ‘Brahmastra’ will be Mouni’s second film in Bollywood; she is marking her debut with Akshay Kumar-starrer ‘Gold’.