Kartik Aaryan, promoting his upcoming film Bhool Bhulaiyaa 3, made a surprise appearance at Alan Walker’s Mumbai concert. The title track, a collaboration with Pitbull and Diljit Dosanjh, has gone viral. Directed by Anees Bazmee, the film features Vidya Balan and Triptii Dimri and is set for a Diwali release on November 1.