J. K. Rowling’s novel Harry Potter and the Sorcerer’s Stone follows the seminal story of three eleven-year-old children named Harry Potter, Hermione Granger, and Ronald Weasley. Together, these three go from being complete strangers to the best of friends through all sorts of adventures they come across at Hogwarts School of Witchcraft and Wizardry. The adventures, both big and small, range from sneaking out of their dormitories past curfew, over rescuing Hermione from a loose troll in the ladies’ bathroom, to saving the day by stopping Him-Who-Must-Not-Be-Named from rising again and ultimately defeating him. Even though the adventures changed each of the named individuals for the better, it is their friendship that went through the biggest and greatest change. In the first chapter, the paper provides a detailed overview of the general notion of character development, which serves as a theoretical basis for the analysis. The changes happening in the novel follow a pattern called The Hero’s Journey which allows all fantasy novels to be original and yet familiar at the same time. Being the main character and prime example of the Hero’s Journey pattern, Harry Potter allows for an in-depth analysis of each individual stage of the Journey. Further analysis sheds light on the character development of the other two important characters, Ron and Hermione, as well as their friendship, which experiences various obstacles during their time at Hogwarts. The conclusion ultimately provides a brief insight in the most important and memorable events and experiences that shaped the novel’s characters.