Mr Hyde: The Monster Within
Hyde literally makes people feel sick just by looking at him. Enfield describes him as "something displeasing, something downright detestable" - notice how Stevenson uses vague language like "something" to create uncertainty and fear. The alliteration of 'd' sounds makes Hyde seem sly and dangerous, whilst his physical appearance represents pure evil that repels everyone he meets.
When Hyde commits murder in Chapter 4, he's described "with ape-like fury... hailing down a storm of blows." This animalistic description links to Victorian fears about devolution - the terrifying idea that humans could regress back into beasts. The weather metaphor of "storm" suggests his violence is both frequent and uncontrollable, foreshadowing how Jekyll will eventually lose all control.
Hyde grows stronger throughout the novella, eventually taking over Jekyll completely. He represents everything Victorian society feared about their own hidden natures - the violent, selfish impulses they worked so hard to suppress.
Key Point: Hyde isn't just evil for the sake of it - he represents the consequences of a repressive society that forces people to hide their true desires.
Jekyll initially believes he can control Hyde, saying "The moment I choose, I can be rid of Mr Hyde." This shows Jekyll's fatal flaw - his hubris and refusal to take responsibility until it's too late. When Jekyll first transforms, he feels "younger, lighter, happier in body" with "not an innocent freedom." Stevenson uses this to critique how society's restrictions can make forbidden behaviour feel incredibly liberating.