There are various possible layers to The Terminator (1984), including:
The transformation is inherently Sarah Conner's. She changes form an innocent to a heroine archetype. This is the basis of the story structure.
Beneath that, there is the Man vs Machine concept, where Man creates a monster (mechanical), which then bites him back. This is similar to Frankenstein etc.
Beneath that, there is the Man vs Nature concept, where Man interferes with nature and it bites him back. Similarly, Man plays God and it bites him back.
Beneath that, there is the idea that Sarah Conner is the Virgin Mary, who is about to give birth to Jesus Christ (John Conner, saviour of the world, both JC), the Terminator is a demon sent by Satan to prevent JCs birth and Reese is an angel sent by God to ensure JCs birth.
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