Is the first part of Mulholland Drive a dream, and if so, whose dream is it?

Is the Zone a literal place with supernatural powers, an alien landscape, or is it primarily a metaphor for the characters' internal struggles and spiritual quests?

Why do the Stalker, the Writer, and the Professor never use personal names, instead being identified only by their roles?

What drives the Stalker to repeatedly risk his life and sanity guiding people into the Zone, even when his own family suffers for it?

Why does the film suddenly shift from monochrome to color when they enter the Zone, and what does this visual change communicate about their journey?

What happened to Haemi, and how much does Ben really know?