The events dominated by Mystery and action in the fourth season follow، After an accident aboard the Enterprise leaves one of its children in grave danger, Data commandeers the Enterprise, driven to take the ship to an unknown origin, where an interesting figure awaits.On a rescue mission to an alien shipwrecked training mission, they discover one of its trainees to be a human.Dr. Crusher's fear of losing loved ones becomes real when her worries create an alternate reality.
