The story opens up on a boy making his way down some rocks to head to a lagoon. A fatter boy with spectacles spots the boy and makes an effort to get to him. The two boys talk to each other and wonder if there are any adults around. Over the course of the conversation, the reader finds out that the boy with the fair hair that the book opens up with is named Ralph. As the two make their way to the lagoon, the reader learns that the fatter, more out of shape boy is called Piggy. Through the dialect, the reader learns that Piggy has asthma and lives with his Aunt.
Ralph enjoys a swim in the lagoon and the two engage in horseplay, It is clear that there are no adult influences on the island and that the boys are free to do what they want. As the story progresses, it becomes more clear that the boys are in some sort of tropical paradise, with palm trees, coconuts and sandy shorelines. The boys banter back and forth, and it turns out that Ralph’s father is a commander in the British Navy and Piggy’s Aunt owns a candy store. Ralph is confident that his father will rescue them from their location as soon as he can.
Fear arises as Piggy tells Ralph that no one knows where they are. The boys find a conch shell in the water and fish it out. The two recognize the value of the shell and realize that they can use the shell to call others to meet. After a few attempts, Ralph manages to emit a loud booming call from the conch. In the next few minutes, many boys appear, called by the conch. Two significant groups emerge as Ralph tells Piggy to remember their names. The littluns are young boys, younger than 10, and then there is a party of boys led by a boy named Jack, who wear matching outfits and march in line. The boys are introduced as a choir of sorts.
The group decides that there should be a chief, and a vote is held. Although Jack wants to be chief, the majority of the group wants Ralph to be chief and he is given the title. Ralph tells Jack he can still be in charge of the choir boys. Jack decides that the choir boys will be hunters. The meeting moves on. Ralph decides that the first order of business should be to see if they are on an island or not. He picks himself, Jack and Simon to make the venture to the top of the mountain. Piggy wants to go but Jack flatly denies him. Ralph tells Piggy to take down names until they get back.
The three start off, first rounding the corner on the beach to only find more beach. The trio then begin to ascend the side of the mountain. This is not easy, as there are pricker bushes everywhere and only small animal paths in the dense undergrowth. The boys horse around a bit, pushing each other and heaving a rock off of the mountain and into the dense forest. Finally, they reach the summit and confirm that they are indeed on a mountain. The boys look at the island, realizing that they are the only ones on it. Simon then makes the three realize how hungry they are. They turn back to go back down to the group. Along the way they find a piglet stuck in the prickers. Jack pulls out his knife but hesitates. The piglet gets away and Jack claims that he was only seeing where to stab it, but the three know that the truth is that the thought of killing is repulsive. Jack vows to stab the next pig he comes across.