Warning! Major spoilers for The Haunting of Bly Manor below.
Early on in the series, The Haunting of Bly Manor's Hannah Grose (T'Nia Miller) is often seen lighting four candles in the chapel to honor the dead. Three are for members of the Bly Manor clan confirmed to be dead — Miles and Flora's parents, Dominic and Charlotte Wingrave, and Rebecca Jessel. At this point in the show, Hannah believes Peter Quint to be missing and not dead. So who is the fourth candle for?
The Haunting of Bly Manor, loosely based on Henry James' The Turn of the Screw, is a ghost story through and through. The second outing in Mike Flanagan's Haunting series follows Dani (Victoria Pedretti) as she takes on a job as an au pair to orphaned children Miles and Flora. She quickly realizes that something isn't right with the house and later learns her concerns about the house are valid because Bly Manor is full of ghosts. The manor is home to ghosts of every variety — kind, vengeful, and those who don't even realize they're dead yet.
Hannah, unfortunately, falls into that last category of Bly Manor's ghostly inhabitants. The show slyly offers many hints over its first handful of episodes that the housekeeper has been dead all along. The audience is meant to figure it out as Hannah does. In the chapel, the fourth candle Hannah lights is done as a subconscious effort to wake her mind up to the truth, but she avoids acknowledging this truth for one heartbreaking reason.
Hannah was dead the whole time — she died right before Dani showed up to Bly Manor when Miles, possessed by the spirit of Quint, pushes her down the well, causing her to crack open her skull. Until the reveal of her death in episode 5, "The Altar of the Dead", Hannah seems a little off. She won't eat or drink, can't sleep well, and often finds herself drifting off. Finally, there's the lighting of the fourth candle. Hannah's act of lighting candles to honor the dead comes from James' novella, "The Altar of the Dead", which is the namesake for Bly Manor's pivotal episode.
That subconscious urge to light a candle for her lost life is her mind's way to attempt to wake her up. But she holds back for one reason — Owen. By lighting that candle, she's not necessarily mourning for her life specifically. Instead, she mourns the life she could have had with Owen, Bly Manor's cook. One of The Haunting of Bly Manor's overarching themes is regret. For Hannah, the regret of not sharing her true feelings with Owen haunts her like a ghost. She tries to hang onto to her earthly life for his sake. But, that fourth candle is a reminder that the moment's over. Hannah's candles are one of the more heartbreaking elements of The Haunting of Bly Manor, but the fourth candle and what it truly represents is downright gut-wrenching.