I think that in each film there is the strongest frame where the character is fully revealed. It's moments like this that make you feel him and live his story.

My Character Drawing
For me, such a big moment was the scene where Laura Palmer confronted Bob. Her look upstairs, filled with horror and despair, makes clear that this is the end and her life is no more.

Details
The viewer understands this through the emotions of the heroine and this is very strong.

Laura Palmer, reference
Work process:

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Done!