The novel by Rick Riordan titled Heroes of Olympus: The Mark of Athena was the focus of this study. The lone journey of Annabeth Chase in the novel was used as an object of the research. Maureen Murdock's heroine's journey theory was applied to analyze the object's validity as a heroine's journey narrative, and the duality that Annabeth Chase achieved by the end of her journey.
This study used qualitative methodology, of which the primary data were extracted from the narrations and dialogues within the novel. The secondary data were concluded from the theory textbook, together with several relevant sources that supported this study. The data were later identified, classified, then reduced to a better nuance.
This study concluded with two results, according to data provided. First result was the applicability of Maureen Murdock's theory of heroine's journey on Annabeth Chase's journey in The Mark of Athena. The study concluded the theory was indeed applicable, for which Annabeth reached every stage in the theory, starting with her departure from Athena, her identification with the masculine, venturing the road of trials, the illusory boon of success, rejecting the negative masculine, descending to the goddess, yearning to connect with the feminine, healing the mother/daughter split, finding the inner man within heart, and achieving duality. The second result was Annabeth's duality at the end of her journey. The study found that Annabeth Chase reached duality, where she reunited with her masculine while mending her feminine regardless of the future that awaited her.

Keywords: Annabeth Chase, The Mark of Athena, heroine's journey, Maureen Murdock, Rick Riordan