Sirius Black told Harry that there were four Marauders. He told Harry that his best friends in school were James, Remus and Peter. He told Harry that there were three unregistered Animagi at the time he was at Hogwarts. He lied. There was another, only one other, who Sirius never mentioned. Perhaps because they had a falling out... perhaps because something happened to her. Rowan Mulciber is the missing Marauder, and this is her story.

During her 7th year at Hogwarts, Hermione is intrigued right from the start by the new Astronomy teacher, Professor John Smith. This strange man has captured all her attention and she seems to have done the same to him. As the year goes by, talking to someone on a more intellectual level becomes something of a drug for her. Letters from Ron become less frequent and conversation with John are more often. The student-teacher wall falls to allow a great friendship to form. But Hermione’s feelings are much more than that. She is falling for the wizard with the metal wand. But an affair isn’t the only thing happening is the castle. Strange things are happening to Hermione that even her great mind cannot explain.