Read The Intruders

Six teenagers from the Bronx set out to explore a cave in their neighborhood. The cave exploration is a washout but after falling down a ledge the six find that they have time-travelled three centuries into
the future. Fortunately, they are accepted by the tribe living there. However, the
tribe is fighting another tribe from Manhattan. These teenagers have a unique
advantage in this conflict. They know the land. For the six, this becomes a
true adventure. Yet, all too soon their adventure becomes very real. Friends
and enemies are getting killed! This was no longer fun. This was war!