SRK and Katrina Kaif were on the sets of KBC for Jab Tak Hai Jaan promotions. The episode was filmed before the demise of the late Yash Chopra. Sony TV and KBC have given a special tribute to Yash Chopra at the beginning of the episode.
Katrina Kaif was playing for a charity called Relief Projects India, which was started by her mother and is for abandoned baby girls in India.
SRK was playing for building India's best cancer research centre in Nanavati Hospital of Mumbai, where he has already opened a special ward for children by the name of his late mother.
Here are the videos of this highly anticipated episode of KBC.
P.S. The videos are in a playlist, so you could just play the 1st video and after it finishes it will automatically go to the 2nd video.