What I love about this episode: Because it’s Sherlock’s dream, Sherlock becomes the person writing the story – it’s his dream, his perception, his subconscious. Except no, he reminds us that John’s the writer, John’s the storyteller, John controls the world’s perception of the two of them.
So there’s a constant reminder of the ambiguity of Sherlock himself: the man in John’s story, vs. the man John really knows. Are we getting John’s story, or Sherlock’s dream? Maybe someone is dreaming, or maybe someone is writing – John narrates the beginning, after all. Which is the real Sherlock: the deerstalker-wearing icon in John’s stories, or the hallucinating drug addict?
Well, both of them are the real Sherlock. Because, as the last shot tells us, 1895 Sherlock is in Baker Street, which fades right into modern-day Baker Street. Both can exist at the same time.
Because EVERY version of Sherlock is equally real. And equally unreal.