y/n is a demigod living with her parents at the Olympus. A sudden event forces y/n to move to London so she can hide from death eaters who try to capture her. For that matter, she has to go undercover with another surname; Grindelwald. She will start to study at Hogwarts along with the marauders but many unexpected things will happen in the way. Will they discover her secret? What will happen at the Olympus? Will y/n be able to pull off her secret identity even if it means hurting people she loves?