As the title of the story implies, Georges is a "mulatto," the product of a mixed-race heritage. His mother Laisa is a slave, raped by Albert, her wicked master with an appalling reputation for treating his slaves badly. As Georges grows up, he naturally wants to learn about the identity of his father, but his mother won't let on, no matter how hard he insists on knowing the truth.
Throughout his childhood, Georges remains ignorant of his father's identity. His mother stubbornly refuses to divulge this information, worried that if Albert should find out, he will have Georges killed to protect his reputation. However, Laisa gives Georges a small deerskin bag which contains a portrait of his father—this is his only inheritance. She makes Georges promise her that he won't look inside the bag until he reaches the age of twenty-five. Georges keeps his promise, but when he takes a peek inside the bag and finds out who his father is, he immediately sets out to take revenge on him.