Adfilmmaker-turned-director R. Balki has voluntarily made four different promos for Amitabh Bachchan's forthcoming film "Bbuddah Hoga Tera Baap" and an overwhelmed Big B says they are the "smartest piece of advertising" that he has ever seen.

Made under Amitabh's AB Corp, the romantic comedy about an angry old man, played by the megastar himself, has been directed by Puri Jagannath. Releasing July 1, it also stars Hema Malini, Raveena Tandon, Minissha Lamba, Sonu Sood, Prakash Raj and Charmi.

"My friend and sympathiser Mr R Balki, who every now and then tests my capabilities as an actor and who has been a great bouncing board, did one of the sweetest things for me. On his own and voluntarily, he went ahead and made 4 promos for the film BHTBaap, without telling anyone, " Amitabh posted on his blog bigb.bigadda.com.

This is not the first time that Balki has collaborated with Amitabh. He made his directorial debut "Cheeni Kum" with Big B and Tabu and also helmed AB Corp's critically acclaimed and commercially successful "Paa".

Both the films had interesting storylines - while the former was about a 30-plus woman, played by Tabu, falling in love with a 60- plus chef, Big B, the latter was about a boy suffering from progeria.

"And I have to say they are the most smartest piece of advertising that I have ever seen. These promos shall be on air soon and they are exceptional ! Absolutely exceptional ! I am so keen to send them out into the cyber world and every channel. Soon then ... they shall be out !" wrote Big B.