Where is Nisha Dastur?

At the onset of her getaway to the hills of Himachal Pradesh in a secluded tourist spot, Writer's Hill, Nisha knew something terrible was going to happen. Less than seventy-two hours later, she goes missing under mysterious circumstances. When the police arrive and question the co-inhabitants, they're surprised at their statements. All of them describe an eerie, almost supernatural, occurrence on the night of Nisha's disappearance.
To add to the strangeness is a unique coterie of travellers-Nisha's ignorant boyfriend, a reclusive but nosy writer and a young couple who are not what they seem. There is also the caretaker's visually impaired daughter who claims she can 'see things'.
With barely any leads, the police know they have to work doubly hard if they want to find Nisha, but with each passing day, the mystery around her disappearance gets murkier.
Where is Nisha?