Padfoot, Prongs, Moony, and Wormtail. AKA; Sirius Black, James Potter, Remus Lupin, and Peter Pettigrew. The four marauders. The infamous pranksters of Hogwarts School of Witchcraft and Wizardry. Well, three infamous pranksters, and one traitor. But that's a different story. What if there was one more? A girl, perhaps? One more tie to Harry's past? Meet Reagan Potter, The Fifth Marauder. She went missing a month before Lily and James were killed, and Harry doesn't know until handed a photograph from Sirius, Reagan's old beau. Piece by piece, Harry and Sirius put together a puzzle, that when finished will tell them where she is, and why she was taken in the first place. Will Sirius be able to find her in time? Will Harry ever meet his aunt?