I think the “evil” was inside every boy, and when they got away from civilization and from adults, the “evil” in all of them came out. As the boys got madder, more evil thoughts and plans come into their heads, and they slowly take over their bodies, causing them to do bad and crazy things to each other. For example, when Robert pulled the lever that caused the rock to roll down the hill, and when Jack ordered everyone to hunt down and kill Ralph, and when the boys murder Simon, because they really want to get rid of the “beast.” They would do anything to have the chance of it gone, even when the “beast” is actually the evil inside all of them, and that when they get scared, or when their life is at stake, the “beast” inside all of them comes