Unfinished at the time of his death, The Mystery of Edwin Drood is nevertheless worthwhile reading, a half of a mystery that hints at the answers, and while you may be fairly sure, even with research into letters Dickens wrote to his friends and biographers, you are never totally sure. It’s a bit like being able to make up your own ending; anyway, it’s just an interesting thing to keep in mind before beginning it.
For the obviously unfinished novel that it is, Dickens does manage to pack a lot of foreshadowing, a dark and menacing atmosphere, and interesting characters. Edwin Drood is an amiable young man long bethrothed to the beautiful Rosa, though after she inherits, they amitably break their engagement. Neville Landless is a hothead in love with Rosa. And though the titular character is the one who eventually disappears into the quicklime, it is John Jasper, a menacing protagonist if ever there was one, a choirmaster who lurks around opium dens, whose story it really seems to be. Is he the murderer? It might seem so. Despite hints, Dickens will keep you guessing. It’s tautly plotted as far as it actually goes though hard to make final judgments on that account.
Finally, a quick note on reading so many Dickens novels in quick succession: while individually they are pretty great, en masse they are exhausting. That is not an experiment that I am likely to repeat.