"'Aatma' is not a horror film, it's a psychological thriller," Nawazuddin, who says he plays an "emotional role" in the movie, told IANS.
The film, directed by Suparn Verma, has an unusual pairing, but Nawazuddin says Bipasha has given one of her best performances in it.
"Bipasha was completely prepared for her role. I bet 'Aatma' will be one of Bipasha's best performances," added the actor, who earned fame for his performance in "Kahaani" and "Gangs Of Wasseypur - Part 1".
Produced by Kumar Mangat and Abhishek Pathak, "Aatma" is currently being shot at a set built at Filmalaya studio in Mumbai.
The project has completed a short shooting schedule earlier at Vashi, Mumbai. The film will also be shot in other locations in Maharashtra, including Panchgani.