Stephen Hawking was on the Paramount lot for the video release of his film A Brief History of Time (1991). He asked the staff "Could you take me out of my chair and put me in the captain's chair?" His request was granted.
Jonathan Del Arco had previously had no exposure to Star Trek, much less the Borg, prior to being cast in the episode "I, Borg." Afterwards, he was keen to return, and pitched several story ideas to the producers, one of which he says was quite similar to the "Descent" story.
The first instance in which the holodeck safety protocols were asked to be disabled. In this instance, Data says it takes two command level officers to disable the safety protocols. In other series, that would change to a single command level officer.
Two starship naming firsts are made in this episode. The USS Crazy Horse is the first named after a Native American, while the USS Gorkon is the first named for a non-Human individual, Klingon Chancellor Gorkon.
The banners inside the Borg fortress display the Borg emblem designed by Rick Sternbach, and first seen aboard the Borg ship in "Q Who" (1989). However the emblem is displayed upside down, reflecting the status of these Borg as renegades from the Collective.
This episode is the third time that the Enterprise-D is commanded by a female officer (Beverly Crusher). Tasha Yar was the first female in command of the ship while Commander Riker was supervising repairs at the holodeck in "The Big Goodbye". Deanna Troi was in command of the Enterprise-D during the episode "Disaster", as the highest ranking officer known to be alive after the ship was struck by quantum filaments.
During the poker game, Einstein has trouble with the math of how much the next bet is. Newton asked if Einstein could do "simple arithmetic". It is a commonly held myth that he could not. In fact, he was quite brilliant as a child, and began teaching himself higher math when he had outpaced his schooling.
In his foreword to The Physics of Star Trek, Hawking jokingly wrote that after "winning" the holodeck card game, he called Paramount Pictures to try and cash in his chips, "but they didn't know the exchange rate."
The matte painting used to portray the Federation outpost on Ohniaka III was with slight changes previously seen as the Darwin Genetic Research Station in TNG "Unnatural Selection" and as the Arkaria Base in TNG "Starship Mine".
The security ensign in the brig is a Bajoran who wears a Bajoran earring. This was referenced in a cut line of Crosis' from the script: "Bajoran. Puncture the lower ventricle of the heart. Death is immediate."
In this episode Data says "I believe I've experienced my first emotion". However, in the episode "Deja Q", Data experiences a brief moment of laughter, which he then describes as "a wonderful... feeling".
The trivia items below may give away important plot points.
Producers originally intended for the cliffhanger ending to be a crash landing by the Enterprise saucer section. However, budgetary constraints resulted in the idea being scrapped, and the crash landing of the saucer would instead be depicted in Star Trek Generations.
In one of the few identical shooting sites used by both TOS and TNG (besides Vasquez Rocks), the oak-studded hillside seen just before Lore's fortress is spotted was the same location used for Spock and Leila's discussion of rainbows and dragons in TOS: "This Side of Paradise".