In a sense, Golding's Lord of the Flies ends as it has begun--with destruction. The boys have arrived upon the island as a result of their plane having been attacked in war and crashing after catching fire. In the final chapter, after having an Eden-like island on which to live with ample food and water, the boys have also waged a war among themselves, dividing into two opposing forces, one of despotic hunger for power, the other of common sense and rationality.
With fire becoming a symbol of the burden of responsibility for Ralph, he becomes the leader after the plane burns; then, he directs the boys in building a rescue fire. However, Jack and his hunters steal this fire, taking away Ralph's leadership and effecting anarchy until the conflicts crescendo into attempts to kill Ralph that create a conflagration that consumes the entire island.
It is at this point that the novel concludes. The island is afire and a messenger from war appears, a British naval officer ashore from a warship (fire and a war machine again). Ironically, he is appalled that Jack looks as he does, painted like a savage.
"I should have thought that a pack of British boys--you're all British, aren't you?--would have been able to put up a better show than that--I mean--"
Ralph looks around at "the burning wreckage of the island." Seeing Ralph weep for the "end of innocence and the darkness of man's heart," the officer politely looks away, but as he does so, his eyes rest on his warship in the distance. His glance indicates that he, too, is well aware of the bellicose nature of man and the "darkness of man's heart."