Ralph and Piggy meet on the beach, having survived the crash. They introduce themselves, then swim in a lagoon. The island - magical place.
Piggy finds a large conch. Ralph blows itand all the other boys who survived flock around. One group arrives in choir uniforms, led by Jack. The boys elect Ralph as their chief, so Ralph asks Jack to be leader of the choir, who will take the job of hunters. Piggy takes names.
Jack, Ralph and Simon explore the island to see if it is inhabited. They push a huge rock off the top of a hill, shouting with delight as it crashes down.
As they scramble back to the others, they see a wild pig. Jack gets out a knife to kill it, but can't quite bring himself to draw blood and the pig scurries away.
Ralph holds an assembly. The conch becomes a symbol of authority - only those holding the conch can speak.
A small boy says he's frightened of a 'snake-thing'. Ralph reassures him there's nothing to worry about, but Jack wants to hunt, just to make sure!
Ralph says there must be a fire to alert passing ships; Jack and his choir rush off to make one. They grab Piggy's glasses to light it with. Jack announces his hunters will keep the fire going. Piggy tries to encourage them to act sensibly. Yet suddenly the fire burns out of control and spreads through the undergrowth.
The boy who spoke up about the snake-things is missing - presumably burnt.
Jack sets off hunting, but fails to catch a pig. He returns to the camp to find Ralph, who has been hard at work building shelters with Simon. Ralph complains the others don't help at all.
Ralph and Jack can't agree what their priorities are - making shelters and getting rescued, or finding meat.
Simon goes off by himself into the dense jungle and worms his way into the thickest part.
Roger bullies three littluns playing, then watches their games. Even they are disagreeing and fighting.
Jack paints his face as camouflage to help him hunt a pig and goes off with his hunters.
Ralph spots a ship on the horizon, but the hunters have let the fire go out, making it impossible for the ship to know they are there and denying them rescue. The hunters return triumphant with a pig, but have to face Ralph's anger. In the argument that follows, Jack breaks half of Piggy's glasses.
They all cook the pig and eat it, although Jack is initially unwilling to share. The hunters are still excited and raise a chant, "Kill the pig. Cut her throat. Bash her in."
Ralph immediately calls an assembly in the darkness. He tries to clarify his thoughts as he prepares for it, and wishes he could think as clearly as Piggy.
At the meeting, Ralph tries to re-establish rules. Then he tries to confront the fear everyone is feeling about a beast. Piggy claims there can be no beast; Simon suggests the beast is 'only us'. The discussion gets more heated, with boys snatching the conch from each other to talk and breaking the rules.
Jack declares he and his hunters will find the beast and starts a wild dance that Ralph is powerless to stop.
Piggy wishes for some grown-ups to keep order. Ralph wishes for a sign from the grown-up world.
Ironically, that sign appears: late that night, a parachutist's body lands on the island, the victim of an aerial battle. Sam and Eric, tending the fire, see the body and believe it to be the beast.
Jack volunteers to lead an expedition to find the beast. After a dispute about whether the signal fire or finding the beast is more important, they set out to the far rocks, the only unexplored place on the island. Ralph bravely crosses to the rock first to confront the beast, followed by Jack. When it is clear there is no beast, the others come, and they realise it is a great place for a fort.
Jack and his followers want to stay at the fort, but in the end Ralph convinces everyone to go back to the mountain and make a fire.
As the party walk back through the jungle, Ralph feels anxious at how dirty and uncivilised he is becoming, and is worried about his position as chief. He dreams of his home, yet Simon reassures him, saying he is sure he will get back.
Jack and his followers approach a pig, but it escapes, then they play at killing a pig - almost too violently.
When night falls, the older ones wonder whether to continue the hunt for the beast or rejoin the little ones. In the end, Ralph, Jack and Roger go on while the others return. They climb through the burnt area of the mountain and when they reach the parachutist's body, the wind makes it rear up. They run away, terrified, thinking it must be the beast.
Now the threat of a beast is more real, the tension between Jack and Ralph increases. Jack calls an assembly, and when the boys vote for Ralph to remain as chief, Jack declares he is not going to 'play' any more and goes off by himself. Ralph and the others, knowing that they can no longer rely on Jack and his followers to keep the fire going on the mountain, start a fire down by the bathing pool.
Jack and his small group kill a pig and leave the head on a stick in a clearing, as an offering to the beast. Simon, hiding in the clearing, sees it all. He stays on when the others leave, staring hypnotised at the bloody head, which is now covered in flies. Jack and his hunters swoop on Ralph, Piggy and the others and steal wood to make a fire for a pig feast. Jack invites everyone to eat meat - if they join his tribe.
Meanwhile, Simon - dehydrated and ill - imagines the pig's head talking to him and mocking him. He has an epileptic fit.
Simon wakes in the night and discovers the dead body of the parachutist. He realises that this must be 'the beast' and, after freeing the tangled lines from the rocks, sets off to tell the others. Ralph learns from Piggy that Samneric and Bill have gone to Jack's group to get meat. They decide to go too, to eat meat and find out what's going on.
Everyone else (except Simon) is already there, laughing and singing. Jack is in the middle, giving orders like a king. He commands his gang to give meat to Ralph and Piggy, then he asks who will join his group. Ralph protests that he still is chief.
The dispute is interrupted by thunder and lightning which makes the boys uneasy. Jack orders them to dance the pig hunting dance - Kill the Beast! Cut his throat! Spill his blood! The chant becomes frenzied, so when Simon stumbles into the middle of the group with his news, they kill him.
The parachutist's dead body is lifted out to sea by the wind and Simon's dead body gently drifts away from the beach.
Piggy and Ralph discuss the events of the previous night without actually mentioning Simon's death, which shows how anxious they are about what happened.
Jack is now a real chief, with a painted face and a tribe of 'savages'. He beats those he's angry with and wields full control.
Ralph, Piggy and Samneric make another fire on the beach to create smoke in the hope of rescue. They feel better when they have completed the work. Ralph relaxes and dreams of home.
Suddenly, the calm is interrupted by Jack and two hunters who invade the shelters and begin a fight. They leave triumphant with Piggy's glasses, rendering Piggy near blind and helpless.
Ralph, Piggy and Samneric hold an assembly with just a few littluns - everyone else is now in Jack's tribe. They are bitter against Jack for having stolen Piggy's glasses, their one chance of rescue. Piggy is determined to get them back, so they set out with the conch. They wish they looked smarter, to prove how civilised they still are.
Painted savages guard the camp while Jack is out hunting. When Jack returns, he argues with Ralph about Piggy's glasses. Jack orders Samneric to be tied up. Piggy bravely takes the conch and stands to speak, despite being able to see almost nothing. He tells the savages to stop acting 'like a crowd of kids', so they become angry. Roger, high on the cliff, heaves a rock loose. It strikes Piggy and kills him. The conch is shattered too.
Jack, unaffected by Piggy's death, claims he is now Chief as the conch is broken. He assumes complete control. Ralph is alone.
Ralph lies hidden and afraid. Everyone else is now part of Jack's tribe. He comes across the pig's head on the stick and, in sudden anger, destroys it with his bare hands.
Ralph meets Samneric who warn him to be careful - Roger is especially dangerous. They help him find a place to hide. He tries to sleep.
Early next day, Jack forces Samneric to reveal Ralph's hiding place. The tribe heave another rock down the mountain near to where Ralph is hidden, but he is not hit. Next they light a fire to try to smoke him out. The fire takes hold.
The situation gets worse and worse - Ralph begins to panic, knowing Jack is out to kill him. He tries to hide, but the savages find him. He bursts out and runs wildly - straight into a naval officer who has landed on the island to investigate the smoke.
The officer is shocked when Ralph says that two boys have died. Ralph claims that he is the leader - then bursts into tears. The officer turns away, embarrassed.