Ismail Darbar’s Tadap Tadap from Sanjay Leela Bhansali’s Hum Dil De Chuke Sanam was the song that has stood the test of time. It is the hallmark of singer KK’s career and with his sudden passing, everyone is talking about this unforgettable number. Ismail Darbar, who was in the middle of a celebration received a rude shock with the news of KK’s passing.