Colonel Mario Toro Lanza is an army colonel in the drug unit whom Thomas meets through a corrupt government contact in another city. At first, Lanza seems easygoing and eager to paid for helping to ensure that Thomas gets his drugs through the La Paz Airport. After the American government orchestrates a crackdown on drug smuggling, Lanza apprehends Thomas and sends him to prison. Years later, Lanza resurfaces in the story as an in-law of two inmates who are involved in an attempt to frame Thomas on drug charges. Colonel Lanza, who started out as an accomplice of Thomas, ends up as his arch enemy in the book.