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.

After living with her aunt and uncle for eleven years of her life, Ellie learns that she is a witch, but at the same time, she also learns of the loss of her only living parent. Her father, who visited often during the summer, is lost during the Battle of Hogwarts. Who is Ellie's father? Wait and see.