At the peak of his power, infamous Medellín cartel boss Pablo Escobar brought in an estimated $420 million a week in revenue, easily making him one of the wealthiest drug lords in history. Escobar, known as the "king of cocaine," saw his wealth grow so immense that he stashed piles of cash in Colombian farming fields, dilapidated warehouses, and in the walls of cartel members' homes, according to Roberto Escobar, the cartel's chief accountant and the kingpin's brother, in his book, "The Accountant's Story: Inside the violent world of the Medellín cartel." "Pablo was earning so much that each year...