Bollywood megastar Amitabh Bachchan says he will start rehearsing for "Kaun Banega Crorepati 4" from Friday.

"Tomorrow (Friday) I start rehearsals for KBC... just getting the hang of things to come, the innovations and the formats. There is still time for its inception, but better to do it now and get acclimatized, than make mistakes later on, " Big B posted on his blog.

Based on the British show "Who Wants To Be A Millionaire?", KBC created history when it was first launched on Star Plus in 2000 with Amitabh as the host. He returned with the second season in 2005, after which superstar Shah Rukh Khan took over the baton in 2007.