"Crito" is a philosophical dialogue written by Plato that explores the nature of justice, friendship, and duty. The book takes its name from one of the main characters, Crito, a friend of Socrates. Overall, "Crito" is a powerful exploration of the nature of justice and duty, as well as the importance of friendship and loyalty in difficult times. It challenges the conventional wisdom of its time and continues to be studied and debated by philosophers and ethicists to this day.