The Neanderthal Man (1953) Scientist invents formula to de-volve animals to a prehistoric state. Naturally, he tries it out on himself. Because scientists are stupid. TIL: Much to the shock of most of social media, the Church actually accepts theories of a God-directed evolution.
Your daily dose of culture courtesy of Gate 2: The Trespassers (1990) - "The cave you fear to enter holds the treasure you seek" - Joseph Campbell