This realization causes Maria to have a complete mental breakdown. Rather than come to grips with reality, she projects her hopes onto a random boy she saw one day - Freder - and lapses into a dream world where he is the central character. This explains the overall fantastic and improbable nature of the events that take place. The heavy symbolism present throughout the film is a sign of the way she sees the world in mythical/Biblical terms, like the parables she tells. It also explains Maria's character decay from independent rebel leader to pathetic damsel in distress; she's overwhelmed by the stress of leading alone and wants to surrender that power to someone else. The robot subplot is an expression of her fear of her own sexuality. The simplistic way everything is resolved reflects her naive view of the world in general and labor disputes in particular.
- This theory is somewhat undermined by the longer restored cut, which adds some complexity to the ending, and also showcases Maria repeatedly risking her life to save others, especially children, even late in the movie.
- The Heart Machine is not the Moloch Machine, though that is not made clear until the rebellion at the end. However, the two are probably connected in some way since the Heart Machine is implied to be central to all of the city's machinery.
- It's red mercury and not blood. The machine is one of the first on-screen concept of an atomic powerplant.
- Now that you mention it, he does spend most of his time stalking the protagonist and his friends, albeit on Fredersen's orders.
- Perhaps this is why all but one of the scenes in which he appears are conveniently missing from any surviving cut of the film...
- Alternatively — if you want to keep Thea Von Harbou's message intact — the actions of Freder and Maria created an alternate timeline where the Bad Future in the Time Machine was avoided.
- Oddly fitting, considering, that the Start of Darkness character-arc for Darth Vader (the definitive example of the relevant trope) as provided by Revenge of the Sith seems to be lifted directly from Rotwang's backstory in Metropolis (Joh's internal monologue even states at one point that though Hel technically died *in* childbirth, she died not from complications but from a broken heart after Rotwang drove her away, a plot device that probably seemed a lot less corny in 1927).
- While this theory sounds quite plausible, (especially since Rotwang is pretty much Freder's Evil Counterpart, while Joh Fredersen is his complete opposite,) there's still the fact that In-Universe, everyone considers it a given that Freder is Joh's son. Thus, the timeline pretty much has to add up... somehow.