1-03: The Naked Now
In investigating the communications loss of the SS Tsiolkovsky, the Enterprise crew contracts an illness that leads to bizarre behavior.
1-06: Where No One Has Gone Before
When engine tests fling the Enterprise to the far reaches of the universe, the crew must rely on a mystifying alien to return them home.
1-05: The Last Outpost
During pursuit of a Ferengi ship, both ships are rendered powerless by an unknown force.