The depletion of the earth's ozone layer causes animals above the altitude of 5000 feet to run amok, which is very unfortunate for a group of hikers who get dropped off up there by helicopter just before the quarantine is announced.

The depletion of the earth's ozone layer causes animals above the altitude of 5000 feet to run amok, which is very unfortunate for a group of hikers who get dropped off up there by helicopter just before the quarantine is announced.