originally named ( The life of Regulus Black ) What if Regulus never really drowned in that cave ? What if he was just magically put in another one's body ? But the only problem was he was in the muggle world without remembering his past self ? That's exactly why the Marauders era and the Golden era are put in a room to watch the life of the presumed to be dead Regulus Black or better yet by his new identity Timothée Chalamet .