- Recycled Set: The appearance of the Yamato, another Galaxy-class starship, means they can just reuse the Enterprise sets. This doesn't necessarily come across as cheap, though, because it arguably makes the Alien Geometries scenes all the creepier for being on a recognisable ship.
- What Could Have Been: The role of Nagilum was planned for Richard Mulligan, but his commitment to Empty Nest prevented him from taking the role. The name "Nagilum" is "Mulligan" backwards, minus one L.
Trivia / Star Trek: The Next Generation S2E2 "Where Silence Has Lease"