It's a Good Movie considering taken the entire movie for sign people, they love it. Apart from that any silent movie should deal with BGM, Camera stillsm slow Mo, Night Vision, etc.. It's good in those aspects.
But the story line was dropped some where, It has no proper reason and justify it in the End. Prabhu Deva sir acted like a Tamil Nadu Terminator. (Hats Off - done his part)
When it comes to Devil/Spirit/Negative forces - Anything is achievable that too a True Blind Spirit which has caused nothing harm in his Life time. He should be able to see the Vision and Control them, anything...Lacked that..& little lengthy..