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The boys have gone to explore the other side of the island, in search of the "Beast" which has the boys gripped in fear, leaving Piggy behind to take care of the "littleuns." The tension between Ralph and Jack is intensifying as each one wants to get the better of the other. Simon, on the other hand, attentive and observant, has noticed Ralph's wistful daydreaming as he wishes for home and order and rescue which, from this side of the mountain, looks increasingly unlikely. The boys are becoming less civilized as time goes by and even Ralph is excited when he stabs a boer with his stick.
Having established (in chapter 7) that the Beast really does exist - or so it seems - the boys squabble amongst themselves and Jack effectively splits the camp in two. Piggy has realized that they can build a fire on the beach and excitement abounds as the boys scramble to get everything for their fire. In the meantime, Jack and his hunters, the remaining choirboys, track a pig and Roger's actions foreshadow the cruelty that will follow.
The "Lord of the Flies" comes into its own when the hunters impale the pig's head on a stick, terrifying themselves in the process and leaving the head in place, symbolically. "The silence accepted the gift and awed them. " The location of the pig's head is also Simon's secret place and Simon sits and contemplates what he now sees. He is acutely aware of the beast in all of them as he "looks the pig in the eye and sees the true beast."
Jack has been able to transform himself behind the painted faces and returns to attack Ralph and Piggy but Jack feels "safe from shame or self-consciousness behind the mask of his paint."
Simon releases the dead parachutist upon discovering him and he is anxious to tell the others about their own fears and the "real" beast. Piggy and Ralph contemplate the possibility of joining Jack's feast so the can have some meat and " make sure nothing happens.” A dispute again arises between ralph and Jack and who should be "chief" and the thunderstorm warns the reader that something terrible is about to happen. In the confusion that ensues as the storm intensifies, Simon is mistaken for the beast as the boys shout "Kill the Beast."
Simon is killed and his body washed out to sea. All of the boys are irretrievably changed and it seems that they have sunk to savagery in the absence of "grown ups." Even Piggy and Ralph have changed as they were unwittingly drawn into Jack's ritual.
It will only be a matter of time before the boys will be totally overcome as, even Piggy's logic and common sense cannot restore them to their former selves.