In "Lord of the Flies" by William Golding, the loss of innocence begins when the characters — all school-age boys — accept the reality that they are alone on a tropical island following the crash of their plane. Without adult supervision, the boys begin to embrace violent behaviors to survive.
The plane on which the boys travel is a British aircraft that was dispatched to aid in the evacuation of British citizens during an obscure nuclear war. The plane crashes on an unidentified tropical island in the Pacific Ocean, cutting a scar through the trees and benchmarking the beginning of the boys' devolution into loss of innocence.
All the adults on board the plane are killed, and the surviving boys scatter across the island as the plane breaks apart during the crash. Piggy and Ralph, two of the surviving boys, locate a conch shell and quickly realize that it can be used as horn to call to the other survivors of the crash.
When the boys join together, they come to grips with the reality of their situation and establish a leadership structure akin to that seen in mature adults. Although the tendency towards structure initially brings all the boys together in a collective effort to survive, the battle for control amongst the boys devolves into savage unrest.
As the struggle continues and another group of survivors is introduced onto the island, the boys continue to shift away from behaving like civilized children. The group begins to form tribes and participate in extreme bullying. Slowly, they become more like the adults responsible for the war that presaged their crash landing on the tropical island; this ultimately culminates in the death of Piggy.