Vin, the street urchin who has grown into the most powerful Mistborn in the land, and Elend Venture, the idealistic young nobleman who loves her, must build a healthy new society in the ashes of an empire. Three separate armies attack. As the siege tightens, an ancient legend seems to offer a glimmer of hope. But even if it really exists, no one knows where to find the Well of Ascension or what manner of power it bestows.