Huck is the most important secondary character in the novel. He is resourceful, inquisitive, and mischievous, embodying the picaresque tradition. Although he perpetrates many schemes and acts that test ethical boundaries, he ultimately shows himself to be a true friend to Jim, using his quick thinking to help him on their journey. Huck is on a quest to understand his place in the world and grapples with the moral questions surrounding the institution of enslavement.

The Duke and the King are two conmen who Jim and Huck encounter during their journey. These characters, inspired by Mark Twain's Adventures of Huckleberry Finn, are swindlers who serve to highlight ethical dilemmas in the novel. They are portrayed as deceitful and racist, willing to exploit and betray Jim, revealing their cruel and immoral nature.

Norman is a Black man who was formerly enslaved and is now passing as white to perform in a minstrel show. His character underscores the importance of friendship in the story and highlights the racist nature of minstrelsy in 19th- and 20th-century America. Despite the personal struggles associated with passing, Norman remains a good friend to Jim, showcasing the humanity and resilience of those who endured racist oppression.