Mark Lombardi, a conceptual artist on the cusp of international success, had everything to live for. So why was the 48-year-old found dead, and his death ruled a suicide? Was it the ultimate conceptual art, an afterlife laugh at those who doubted his brilliance? He did, after all, carry business cards eerily portending "death defying acts of art and conspiracy." Or was he ultimately overwhelmed by the subject of his work: the financial networks connecting some of the most powerful and corrupt people on earth? His intricate drawings traced hot money, from Cold War funding to the heroin...