Chapter One begins by introducing Ralph and Piggy, two boys who are stranded on an island.

Piggy claims that he had been flying in an airplane, when he looked out the window, and saw that the plane was on fire; it is assumed that the plane was bombed down, since the book takes place during the dawn of World War II.

Ralph is the first boy to climb out of the plane, and explore the jungle. But, shortly after this, he meets Piggy, another boy who's stranded on the island. Ralph doesn't pay much attention to Piggy, who rambles on about how the plane was on fire, and how he thinks they were attacked. Ralph is more interested in the fact that there are no grown-ups. He takes great pleasure in this, standing on his head, and grinning. It's obvious he takes great delight in the fact that there's no one to boss him around.

Later, when Ralph is on the beach, he takes off all his clothing, and stands out, looking at the water. Piggy soon joins him. After a while, Piggy reveals the nickname he was given at his school, and Ralph laughs hysterically. Piggy tries to calm Ralph down, but Ralph can't stop laughing, and teasing the thoroughly embarrassed Piggy.

After this, Ralph and Piggy find a conch shell buried deep in the sand. Piggy gets excited over the shell, blabbing on about how you can blow into it and make a loud, booming noise. Ralph becomes interested in this remark, and tries, unsucessfully, to blow into the shell. The shell makes a sort of farting noise, and makes both boys laugh. But then, Ralph concentrates really hard, and blows into the shell at the top of his lungs. A huge, booming noise shakes the island, sending birds flying into the air, and animals squealing into the underbrush. The noise attracts boys from all over the island. At first, only smaller children begin to appear, but soon, older children begin to arrive. All of them gather around Ralph, waiting for him to speak to them, as if he's their leader. Shortly after this, another group of boys appear on the horizon. When the boys arrive, they claim to be "the choir", and reveal their leader to be Jack, an authoritive, snobbish boy. There's a bit of discussion over who the leader is to be, but, after an intense vote, Ralph is chosen as the new leader, leaving Jack furious. Ralph, wanting to avoid an arguement, puts Jack in charge of the choirboys. Jack is pleased at this, and suggests they become hunters, and Ralph quickly agrees.

After the situation is cleared, Ralph, Jack, and another choirboy, Simon, wander off into the forest, excited to explore the island. They fight through the thicket, and reach a rocky peak on the island. They look out, and find that they are surrounded by ocean on all sides. On their way down, Jack spots a pig stuck in a tangle of vines. He pulls out his knife, and gets ready to kill it, but he hesitates, obviously overwhelmed at the thought of taking away the life of a living creature. His hesitation gives the pig enough time to scramble away, and run off into the forest. Jack is embarrassed at his hesitation, and claims that he was looking for a place in which to stab the pig, but the other boys know the real reason he didn't kill it.