The film centres around a recluse, locally known as 'Colonel', played by Shah, who lives with his large German Shepherd dog in a lush green deserted estate on the high altitudes of Vagamon, Kerala.
Kurian says the 'Ishqiya' actor has portrayed a never-before-seen character in the thriller.
"He is an unbelievable actor. This will be considered one of his greatest performances in cinema. How often do you see Naseer sir with a gun, in an unusual character like this? This will be a new experience even for the audience to watch him like this. He will surprise everyone," Kurian told PTI.
'The Blueberry Hunt' focuses on how the Colonel's plantation of a high potency variant of marijuana - Blueberry Skunk - gets ready for harvest but things go haywire at the last moment.
Kurian, who had earlier directed the Atul Kulkarni starrer critically acclaimed 'Manasarovar', said the 66-year-old actor performs in his own space and was happy that Shah agreed to do the film for free.
"Naseer sir acts in his own space, there were many occasions where I didn't say cut because he had gotten into his flow, which I didn't want to interrupt. I was thinking to keep the film at one-hour thirty minutes, but in the end we have a one hour fifty five minute movie," he said.
"He agreed to do the film for free. He loved the story I narrated to him. I had decent money to produce and Naseer said let's do it. Since I produce films myself, it takes me a lot of effort to find funds, do a decent campaign and release it," Kurian said.
The film is scheduled to release theatrically on April 8 and will also be available for paid digital download the same day.
Kurian keeps shifting back and forth to US, designing software so that he can make enough money to fund his films.
He feels getting into production for an off-beat film can be a bit tricky, but is happy that there is audience today waiting to watch small movies.
"Getting into production, finding distributors, doing the right marketing is very difficult, especially if you are an outsider who does not know how this functions. Thankfully, there is a large audience today who are ready to lap up small, unconventional films," he said.
"I am hoping that my target audience watches the film. It becomes important for movies like these to break even at the box office, so that not enough money is lost. One can go back to fund his next movie easily," Kurian said.
'The Blueberry Hunt' also stars Vipin Sharma, Aahana Kumra among others.
