The Guy Fawkes mask used in the film V For Vendetta has a cultural and historical context. Moreover, Hugo Weaving's operatic body language and his hypnotically chiming British accent lent it a charm of its own. Ism borrows the mask, and strips it off its context and aura.
That's forgivable if it is used just as a mask, but we see it turn into an emblem and a flag of the revolution this film is centred on. It feels just like meeting one of those Pawan Kalyan fans wearing Che Guevera T-shirts. And this appears only as a minor problem compared to the film's script.