Let me call on stage Alia Bhatt who now knows who the President of India is," said Karan Johar in his characteristic sarcasm-laced wit, taking on his chat-show host avatar. "One second, Karan, do you know the full form of MNS?" interrupted a sharp-toned Twinkle Khanna, managing to keep a straight face. "I only know the full form of PMS. Which is what I’m going through these days," was his prompt repartee.