n the events of Last Order, taking five years before the beginning of Final Fantasy VII itself, Sephiroth was ordered to inspect the Mako Reactor outside the town of Nibelheim with a small entourage, consisting of one other member of SOLDIER and a few Shin-Ra MPs. Among this group was SOLDIER 1st Class member Zack and his buddy, a 16-year-old Shin-Ra trooper named Cloud Strife.

Overview from themoviedb.org