Dr. Henry “Harry” Jekyll/Mr. Edward Hyde

Dr Jekyll is a "large, well-made, smooth-faced man of fifty with something of a slyish cast", who occasionally feels he is battling between the good and evil within himself, leading to the struggle between his dual personalities of Henry Jekyll and Edward Hyde. He has spent a great part of his life trying to repress evil urges that were not fitting for a man of his stature. He creates a serum, or potion, in an attempt to separate this hidden evil from his personality. In doing so, Jekyll transformed into the smaller, younger, cruel, remorseless, evil Hyde. Jekyll has many friends and an amiable personality, but as Hyde, he becomes mysterious and violent. As time goes by, Hyde grows in power. After taking the potion repeatedly, he no longer relies upon it to unleash his inner demon. Eventually, Hyde grows so strong that Jekyll becomes reliant on the potion to remain conscious throughout the book.