Karan Johar`s Kalank has been the talk of the town as fans are eagerly waiting for its release. The second song of the film was launched by Varun and Alia in Mumbai. The second song of Karan Johar`s magnum opus Kalank was released among much fanfare at an event in Mumbai. The song titled First Class was launched at the Gaiety Galaxy theatre in Mumbai with Alia Bhatt and Varun Dhawan gracing the occasion. Varun and Alia`s 4 film old chemistry was evident as they performed on the song in front of the media and fans. Alia even performed impromptu on her song Ghar More Pardesiya, also from the same film. It must be like a deja vu for the Varun and Alia as Before Kalank, they were launched together by Karan Johar with Student of the year. After that they were seen together in Humpty Sharma ki Dulhania and Badrinath ki Dulhania. The crowd was enthralled by the lead actors and their chemistry when they climbed up the balcony of the cinema hall and interacted with the fans who gathered there in huge numbers. Alia was wearing a black churidaar and white chikankari suit while Varun was wearing a black Kurta pyjama. Kalank will be releasing in theatres on April 17.