sentences:  "Metropolitan" and "City on Fire" were published by HarperCollins, a result of Williams attempting to move to a publisher that would pay and promote him better than Tor Books, his previous publisher.However, his editor was fired and the HarperPrism line cancelled soon after "City on Fire" was published.As a result, Williams would not be able to have a third volume in the series published without retrieving the rights for the first two and finding another publisher for them, along with the third book.