WARNING: Spoilers for The Haunting of Bly Manor.
The final episode of The Haunting of Bly Manor, "The Beast in the Jungle", reveals that the narrator (Carla Gugino) is Bly Manor's gardener, Jamie, and she’s attending the rehearsal dinner for Flora’s upcoming wedding. However, adult Flora doesn’t have an English accent. Instead, she sounds American. This detail helped hide the ending twist and kept the storyteller’s and the bride’s true identities a mystery until the end. Does it make sense that Flora doesn’t have her accent anymore? Two factors might help explain what happened to make her accent disappear.
The Haunting of Bly Manor opens with the narrator going to a rehearsal dinner where she begins to tell a long, sad ghost story to the other guests, including the bride and groom. At first, the identities of these characters—especially the bride and the narrator—are not clear. All that is known is that the wedding is taking place in Northern California in 2007 and that the narrator has a heavy English accent, while the rest of the episodes are set in the year 1987. The truth only comes out during the last episode of the season, when what happened to everyone after the haunting events that took place in Bly is revealed in one of the series' most bittersweet moments.
After saving Flora and allowing the Lady of the Lake to possess her, Dani and Jamie travel the world together, while Uncle Henry takes Flora and Miles to the United States. This would make Flora about eight years old when they moved away from England. At that age, accents can fluctuate a lot, and they only really settle during puberty. By the time Jamie meets up with her again as an adult, Flora has already spent most of her life in the United States. Growing up in another country usually means going to school and interacting with children on a daily basis—and these children likely had American accents—which probably influenced Flora’s own accent and voice. Children are sponges for knowledge, so that explains why she would pick up a new accent over the years.
However, there’s also another possible explanation — one that comes from the show. When catching up with Owen, Dani and Jamie learn that Miles and Flora have lost most of their memories of Bly Manor, barely remembering the place. They have no clue about all the ghosts in the manor and can't recall what happened to them during the years of their childhood spent there. If their early memories were so affected by possession and time, it would make sense that their accents would also easily disappear while growing up in another country. The less they remember about England, the easier it is to be influenced by the accents of the people surrounding their new life.
In the end, Flora’s American accent helped hide her identity from the audience, making for a fun reveal at the end of The Haunting of Bly Manor. In a show full of hidden clues to its biggest twists, Flora’s accent might’ve thrown off even the most attentive viewer, keeping everyone guessing until the very last scenes. Flora starting a new life despite the traumatic events she faced when young also added the sweet part of the bittersweet, tragic tale of Dani and Jamie's doomed romance. And, while tragic, Dani’s sacrifice truly helped Miles and Flora find happiness in their lives.