Siddharth will make his debut with HUMPTY SHARMA KI DULHANIYA which stars Varun Dhawan and Alia Bhatt. ''Siddharth will play an important role,'' says a source. Karan Johar confirmed the news and said, ''Yes. Siddharth has been signed up for the film. He is a talented actor and a rage in 'Balika Vadhu'. Dharma Productions plans to continue its professional equation with him.''