In the beginning of the movie, Mahesh believes that he had killed two of the villains and kills Kelly believing he is the last one. As he is desperate to know who his parents are, why didn't he imagine asking Kelly about his parents before killing him?
shareCoz, he is imagining killing these three people; as they have been registered in his troubled childhood memory as the murderers of his parents. An you don't reason in your dreams/imagination.
shareWell, the first time he gets brain scan and finds out his brain is creating delusions is after the first fight. My guess is that since he didn`t know he is delusional he never really thought about the fact that he doesn`t really know anything about his parents and doesn`t even remember their faces. He starts to think about only when the doctor states the obivous.
share