Knock Knock…Kaun Hai?

On the night of a college party, in a fit of anger, Tanya downloads the Knock Knock app and puts a death wish on Mehek setting off a series of unfortunate events.

Tanya is blackmailed into a task for the Knock Knock Killer as Mehek is found in a near death condition.

Tanya meets a mysterious and brooding stranger - Adheer. Knock Knock warns Tanya that someone close to her will pay for the task she left incomplete.

Tanya is chased and pulled under water as the Knock Knock Killer attacks her.

The gang discovers Adheer dragging Tanya out of the lake. Is he the killer or her savior?

Tanya finds an ally in Adheer who believes in her. At the vigil for Mehek, a shocking arrest is made.