Synopsis :
Hawa begins with a divorcee Sanjana (Tabu) moving into her new bungalow in Manali with her two kids, younger brother (television actor Imran Khan), and a dog. However, the whole bungalow has an eerie atmosphere to it and strange things begin to happen in this otherwise peaceful surrounding.

On the first night thunderstorms hit the area and lightning strikes next to her compound. Soon Tabu, her brother, and his faithful dog start hearing and seeing 'airy' things. In no time, the dog is possessed, goes missing, returns the next night and attacks its master Sanjana.

It turns out that the house is haunted by some invisible spirit that takes liking to Sanjana and then rapes her.

A shocked and phobic Sanjana rushes to the house of her friend Pooja (television actress Grusha Kapoor). But Pooja's husband does not want them in his house, therefore Sanjana has to return to her bungalow.

Pooja refers Sanjana to a psychiatrist [Shahbaaz Khan], who does not believe she is being raped by an invisible ghost and considers her to be a case of a split personality.

Things move from bad to worse when Sanjana is raped in front of her kids one night. On another night, while returning from work, the spirit attacks her again and worse, it even takes away her youngest daughter.

Soon Tabu consults a psychiatrist-exorcist (Mukesh Tiwari) who she thinks can solve problem. The rest of the story traces her efforts to get her daughter back and solve the mystery.