The crew of Voyager discovers an unusual object floating in space while following a particle trail. They then land on a planet and discover an old Earth aircraft and then are led to a cave that contains cryogenic units with people from Earth in them.

The ship's holographic doctor has a strange encounter with Lt. Barclay that leads to him having problems telling reality from fiction. He is lead to believe that Voyager is nothing but a holographic simulation that he must fix.