The 71-year-old termed the process of making him look younger "hilarious" and "inconvenient".
"The desperate attempts to make me look 20 years younger for the sequence at the shoot, was hilarious... To say the least!! How conveniently easy it is to age rapidly, but how inconveniently long it takes to push time back," Bachchan mused on his blog.
The megastar also shared the result of the process by posting his youthful photographs.
"And now that all have carefully suppressed their giggles and snide asides, it is time for me to seek my time with the pillow," he added.
They later reunited for the show, which will mark Bachchan's fiction debut on TV.
It is not for the first time that Bachchan has altered his appearance in such a drastic manner. He played a 13-year-old progeria suffering child in 'Paa'.