Mr. Hyde and the setting that can be used to suggest the evil nature of this person and how, with hindsight, he represents the evil side of Dr. Jekyll. Note the description of the "sinister building" that Mr. Hyde leaves from:

It was two storeys high; showed no window, nothing but a door on the lower storey and a blind forehead of discoloured wall on the upper; and bore in every feature, the marks of prolonged and sordid negligence. The door, which was equipped with neither bell nor knocker, was blistered and distained. Tramps slouched into the recess and struck matches on the panels; children kept shop upon the steps; the schoolboy had tried his knife on the mouldings; and for close on a generation, no one had appeared to drive away these random visitors or to repair their ravages.

Note how the setting reveals so much about Mr. Hyde's character. The building is "sinister" and presents a "blind" face towards the outer world, hinting at the hidden identity of Mr. Hyde. The door is "blistered and distained" just like Mr. Hyde's character, and the random visitors and their varioius "ravages" that they cause on the building hint at the evil that lies therein.