Oscar Isaac hired his brother as his Moon Knight stand-in to help him play his dual roles

Gizmodo

Isaac's role as Steven Grant/Marc Spector, a superhero with dissociative identity disorder powered by ancient Egyptian myth, required him to act opposite himself. To make it work, Isaac hired his brother. “Well, the first step was to hire my brother, Michael Hernandez, to come in and be the other me, it’s the closest thing to me there is,” Isaac said at Moon Knight’s global press conference. “So he came in and he would play either Steven or Marc, even with the accent and everything—both accents. That was really helpful to have someone that’s not only a great actor, but also shares my DNA to play off of.” ALSO: Even Marvel was confused by Isaac's Moon Knight accent.