WARNING: The following contains major spoilers for The Haunting of Bly Manor, streaming now on Netflix.
"The Altar of the Dead" is The Haunting of Bly Manor's most breathtaking but confusing installment. Similar to Hill House's standout hour, "The Bent-Neck Lady," this episode provides a mind-bending POV from one of Bly Manor's ghost residents. But unlike its predecessor, this episode offers more questions than answers, so let's make sense of what's going on.
Something's wrong with Hannah Grose. Throughout the first half of Bly Manor, the housekeeper always seems a little off. She never eats or drinks, always complains that she's had a poor night's sleep and constantly appears to drift off. "The Altar of the Dead" offers up a reason for that odd behavior -- Hannah has been dead all along. The horror series gets to this resolution in a roundabout way as it twists and turns through time over the course of the episode.
While it isn't clear at the time, "The Altar of the Dead's" trippy method of storytelling gives way to one of the most important elements of the central ghost story. The reveal also ties the story back to its predecessor in a thematic way.
In the episode, Hannah relives key moments from her time at Bly Manor all at once; specifically, memories of Owen and Charlotte Wingrave, Rebecca Jessel and Peter Quint. But it's those moments with Owen that act as her anchor. She relives the memories out of order but is always taken back to the day she interviewed Owen for his position at the manor. It's through talking to her subconscious manifesting as Owen that she realizes she's dead and has been since a possessed Miles pushed her down a well.
This episode is intentionally confusing as it reflects Hannah's current state of mind. Anyone who dies on the grounds of Bly Manor remains trapped there after death. As evidenced by the show's hidden ghosts, spirits can reveal themselves to the living residents of the manor. Hannah still goes about her daily life because she hasn't accepted that she's dead. She falls out of time because she's slipping away. It's something that Bly Manor adds to common ghost lore. Multiple ghosts on the show are shown doing this because it's the first step in a ghost losing its sense of self and becoming a faceless ghost like the lady in the lake.
The Haunting of Hill House already established that ghosts in The Haunting series experience time in a different way than the living. But Hannah's journey offers a sentimental connection to that idea. While the dream-hopping that Hannah and the other Bly Manor ghosts experience doesn't happen in Hill House, one ghost is shown falling through time. Nell Crain dies at the beginning of Hill House and meets with her siblings one last time during Hill House's hopeful ending. She tells them that she's always with them, even in death. Memories of her fall around them like confetti.
The same idea is deployed in Bly Manor. In fact, show creator Mike Flanagan confirmed that, on multiple occasions, both Hannah and Owen were going to compare memories to confetti. While it may be the same idea from Hill House, Bly Manor uses it in a more heartbreaking manner. In Hill House, Nell uses the idea to help her siblings accept both her death and their mother's. But for Owen and Hannah, the confetti metaphor is a stand-in for what could have been. They don't get the love-filled moments the Crain siblings had. Their moments are stolen glances and unspoken words. "The Altar of the Dead" is a loving answer to Nell's confetti speech. The Haunting of Bly Manor simply uses it as a reminder that love looks different to everyone.