Peter Cool, an advertising agency employee, recently and secretly married (what he already considers unsuccessful) to Alice, the daughter of his boss, learns that his brother Gideon, working as an engineer in Guatemala, has been accused of the murder of a certain Maria Delgado and is being held in prison and will most likely be executed without trial. Peter learns about all this from Seraphina, Maria’s sister, who came to Philadelphia for a letter that Gideon was supposed to send to his brother. But others are also hunting for the letter... Trying to help his brother, Peter goes to Guatemala...