Mumbai,  Bollywood stars make it a point not to promote each other's films, but South Indian stars are used to giving shoutouts to each other's work and stand by the principle of swimming or sinking together.

In the recent past, Chiranjeevi, S.S. Rajamouli and Nagarjuna promoted Aamir Khan's 'Laal Singh Chaddha', and stars of the Tamil industry, too, were generous in their praise for the film.

The same spirit of camaraderie has been evident in the 'Brahmastra' promotional blitz, which is being led by two people who understand how social media works -- Alia Bhatt (fresh from the warm reception accorded to 'Darlings') and Karan Johar, a co-producer of the epic film.

After Rajamouli and Nagarjuna (who is making his Hindi cinema debut with the film) joined its lead character, Ranbir Kapoor, to promote the film in Chennai, it is Jr NTR, whom Karan Johar described as a "man of the masses" in a recent tweet, will join the 'Brahmastra' cast for the Hyderabad blitz planned for September 2.

Johar not only made the announcement, but also ran a video that combines motion picture images of Ranbir Kapoor, Alia and Amitabh Bachchan with action scenes of Jr NTR from 'RRR'.

Announcing the Hyderabad event on Instagram, 'Brahmastra' director Ayan Mukerji wrote: "NTR for Brahmastra. Through the journey of this movie, there have been some very big personalities and achievers who have left me short of words with their generosity towards us. Another such Star in Brahmastra's Sky is now NTR who is going to shine bright as he always does, at our movie's biggest event in Hyderabad!"

He added: "Coming together with Ranbir, Alia, Nag Sir, our Team, and of course Rajamouli Garu, for whom my love, respect and gratitude has no boundaries. So excited about Tarak giving Brahmastra some love and energy, and helping us take our movie into the Telugu Universe."

Even as industry watchers wonder when Bollywood will emerge from a particularly difficult year, all eyes at the moment are on what transpires at Ramoji Rao Film City, Hyderabad, on September 2.