Anyway, his solution, as a doctor, is to find a medicine that will allow him to split his personality into two—when he's Dr. Jekyll, he's overwhelmingly good but also slightly bad; when he takes the drug, he's Mr. Hyde, and he's all bad. (Where does the good disappear to when he does this? Is the new Dr. Jekyll actually ALL good, since Mr. Hyde was ALL bad? The novella won't say, leaves it deliberately open. There are some interesting arguments about Calvinist stuff in here, I think—and Stevenson was raised in Scotland, so he certainly had room and biographical background to make these arguments. But he won't, because he's not from the seventeenth century—poo on him.) Mr. Hyde does several appalling things, like walking directly over a small child in the street when Mr. Utterson meets him for the first time. (It's not clear HOW you just walk over an 8-year-old, but because this is also a horror novel, the unimaginability of this act makes it terrifying.) But Jekyll learns that splitting himself is dangerous—shades of nuclear bomb-making, shades of Voldemort and his horcruxes (although of course the influence goes the other way—but it's what I'm thinking)—because eventually he can't stay Jekyll: he keeps turning involuntarily into Hyde. (It's not clear that Hyde really gets to have much fun when he's in that persona, either—mostly he seems to stay in his room, snapping at the servants, and making himself tea. When he goes out, he just walks over little kids, and once murders an M.P. Where are the whores? Where's the ludicly evil fun that being Hyde was supposed to allow???) Meanwhile, Jekyll/Hyde's building up a tolerance to the drug and needs more and more of it to switch, which is complicated by the fact that he can't get a supply of the precise strain of it he was using when he started all this mess. So on one level, this is just a story about opiate addiction (that was how I read it when I was ten—I'd picked the book up in the library, but understood it as an extension of the D.A.R.E. program). In the end, Jekyll can't hold off turning into Hyde any longer; he fixes himself a beaker of the stuff and is about to drink it, but dies in the process of his transformation.
So what happens to the self? When Jekyll is dead, so is Hyde (and had Hyde died, Jekyll would have to, too). Stevenson isn't going to offer any answers. Instead, I think, he wants to just set up something horrible—gothic—that's self-explanatory up to a certain point, but also has certain gaps in its explanation of things. These gaps are terrible, because they're spots where an explanation of the self should go, and instead there just isn't anything there.
