mimic
A standard trope in the genre is a nagging uncertainty about whether the double is real at all. Is this actually an identical stranger, or are they a long-lost twin?
Naomi Klein • Doppelganger: A Trip into the Mirror World
D'arcy Wretzky - Wikipedia
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Émilie Sagée - Wikipedia
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lookalike
Gothic double - Wikipedia
William Wilson (short story) - Wikipedia
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Murder ballad - Wikipedia
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The Crane Wife
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Elliott Smith
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