A lot of people misspelt the title of the book and called it Necropolis, but I'm fine with that, because the title is a play on that and it is a city of the dead. Narcopolis is a necropolis. Bombay disappears and a lot of the characters die with it. Throughout the book, opium disappears and heroin arrives and the last few chapters point at the future, to what Bombay will be. You can make an accurate educated guess as to what it will be in the future.