Charles Dickens is like William Shakespeare: most of his stories are timeless, and can be transplanted into any setting. Take A Christmas Carol for example: it can be a drama, a motion-capture animated adventure, a 1980s Bill Murray comedy, a musical with Muppets, or a movie where Ti West makes him into a kind of anti-hero, for some reason.
But not every story is so universal, and that makes them harder to adapt. A Tale of Two Cities, for example, is set at a very precise moment in time: the best of times, the worst of times, the age of wisdom, the age of foolishness, the epoch of belief, the epoch of incredulity, you know the rest. Basically, it’s the French Revolution.