Amitabh Bachchan has lent his unique baritone for Hrithik Roshan-starrer 'Krrish 3' at the behest of filmmaker Rakesh Roshan

"Up at 7 a.m. to reach for a dub for 'Krissh 3'... Rakesh Roshan, father to Hrithik and the director and producer of eminence, asked me to do a voiceover for his film... I agreed and that was done," the 70-year-old posted on his blog srbachchan.tumblr.com in the wee hours of Saturday morning.

Hrithik plays a superhero in this third film of the franchise which began with 'Koi Mil Gaya' in 2003, followed by 'Krrish' in 2006. 'Krrish 3' is slated for release on November 4.

The film also stars Priyanka Chopra, Kangna Ranaut and Vivek Oberoi.

Meanwhile, Big B is also geared to launch the forthcoming season of his hugely popular reality game show 'Kaun Banega Crorepati'.