New Delhi, Mar 06 (ANI): After piquing fans' curiosity by sharing the glimpse of 'Brahmastra's' logo in the sky at the concluding day of Kumbh Mela, the official logo of the film is finally out. Alia bhatt took to her Instagram to unveil the logo. The powerful voice of Amitabh Bachchan introduces the logo to Ranbir and Alia. In the video, the trio can be heard talking about a mysterious weapon as the brahmastra logo takes form. According to the legends, Brahmastra is a hindu god Brahma's weapon that is so strong to destroy the universe. Brahmastra has been extensively been shot in Bulgaria, New York and Mumbai among other places . Apart from Ranbir and Alia, the film starts Amitabh Bachchan, Mouni Roy and Tollywood actor Nagarjuna. 'Brahmastra' is first part of a sci-fi trilogy which has been created by Ayan. It is slated to release around Christmas this year.