First things first! Before we dissect the film, discuss its merits and demerits, discuss whether it worked or not and offer reasons, let's salute the grit, determination, willpower and courage of Nasser Khan, who enacts the role of the protagonist in Shadow. Imagine a blind person carrying off those hazardous, death-defying stunts... Just that effort deserves an applause.
Now let's come to the point. Shadow is more of a showreel to project the acting abilities of Nasser Khan, so, expectedly, the writing takes a backseat. The screenplay is very '70s and '80s, reminiscent of the masala films we enjoyed so much then. It's just that times have changed and so have the tastes of a big chunk of moviegoers. Yet, there's no denying that there still exists a sizable chunk of movie-going audience that relishes masala films and Shadow is targeted at them.
The police have not been able to crack a serial murder case. Arjun Sherawat [Nasser Khan] is a man who is unseen and is the criminal. No one knows his identity. This case has been granted to Sanjana [Sonali Kulkarni], a police officer. She has been trying too hard, but all her efforts have been in vain.