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.
1-01/02: Encounter at Farpoint (Parts 1 & 2)
On its maiden voyage to explore a new trade station, the crew of the Enterprise-D are delayed by an omnipotent being who views humans as inferior and non-worthy of space exploration.
1-05: The Last Outpost
During pursuit of a Ferengi ship, both ships are rendered powerless by an unknown force.