First of all, if you are having a background of Bihar, then why the dialect was used was that of UP. Filmmakers should understand that UP and Bihar have different dialects for Hindi. At least one of the actors was good with the language, Dhanush. His performance carried the film throughout. Sara seemed confused about the dialect all the time and thus her performance dipped. Akshay kumar must have been roped because of his good Fan following in North, otherwise there is nothing much for him to do in the film.