A number of English school boys suffered from a plane accident causing them to get stranded in an uninhibited island. The period was maybe during the World War II. Trying to be civilized, they elected a leader for themselves as well started the division of tasks (hunters, fire-watchers, etc). Things turned bad when there's a power struggle between the group leaders, worsened by various sightings of a monster in the island. No, don't think about "Lost" because this is way different.