“Dark Frontier” is episode fifteen of season five of Star Trek: Voyager.
The episode opens with a Borg vessel activating drones after detecting another vessel – Voyager. They give Voyager the usual spiel about being assimilated. Captain Janeway responds that the Borg know they can match the Borg’s firepower. The Borg vessel is quite small and, whilst they are reconfiguring their shields, a photon torpedo is beamed aboard. The Borg fail to disarm it in time and the Borg ship explodes.
On the bridge, Chakotay says he thought they were trying to disable the vessel. Seven of Nine replies that the torpedo detonated near a power matrix and caused a chain reaction. The captain wants the debris field salvaged; there may be something they can use.
The captain enters the cargo bay where the Borg vessel is the way she prefers them – in pieces. Chakotay tells her that B’Elanna has found a transwarp coil. Janeway thinks the Borg might think twice about attacking them. Chakotay responds that the ship was only a probe; next time it might be cube. Harry warns the captain to put down a piece she’s picked up and the Doctor has the servo arm from a medical repair drone that he’s really excited about. Seven and B’Elanna are working on the transwarp coil, but it’s non-functional; Seven states that, when a Borg vessel is critically damaged, vital technology self-destructs. She does have some data nodes, one of which has details of Borg ship movements in a 30-lightyear radius.
Janeway and Tuvok are in astrometrics where Seven is showing them Borg tactical movement across 25 sectors. There are three cubes that are not a threat and a heaving damaged scoutship, a Borg sphere, that is regenerating. Janeway wants that one. In the briefing of the senior staff, the captain explains that she’s basically planning a heist. One transwarp could would shave 20 years of their journey. The sphere is damaged enough that they could get in and out, but there is no margin for error. They will need a diversion so an away team can get the technology. Chakotay says they can recreate parts of the sphere on the holodeck to practice. The captain says it’s time to assimilate the Borg.
In the captain’s ready room, Seven states the plan could succeed. Janeway replies that Seven’s parents could help with that. They have the records of the Raven, which spent some time studying the Borg. Any tactical edge would help. Seven replies that her parents were assimilated; their tactics were flawed. Janeway is willing to assign the research to Chakotay, but Seven says she will do it.
Neelix brings the records to Seven’s cargo bat. He asks if it’s true her parents were studying the Borg. Yes; they were exobiologists. Neelix thinks they were courageous; Seven that they were misguided. Neelix is envious of the amount of records Seven has; all he has of his family is a faded holoimage of his sister.
Seven starts reading the records. Young her – Annika – is playing with a Borg cube model when her father enters and says that it isn’t a toy. They are leaving on a voyage tomorrow, going to see the Borg. Annika asks if the Borg are friendly. Her father states they are different. No, they are not friendly. Eight months later and they haven’t found the Borg, and Erin Hansen is telling her husband they need fuel when a transwarp conduit is detected. It’s a Borg cube and they are excited to see it. Not the reaction of most when seeing a Borg cube. The cube scans them but ignores them and Magnus Hansen thinks it could prove his theory. The Borg ignore any lifeform until they consider it a threat. Or a target.
Now, parts here don’t make sense for the time. When the Enterprise encountered the Borg in the TNG episode “Q Who?” the Borg were unknown to them. The Raven left the Federation before the Borg were known about at the time, and it seems clear the Federation knew the Hansens were seeking out the Borg. The Star Trek: Enterprise episode “Regeneration” later showed that, thanks to the events of First Contact, the Federation did know about the Borg earlier, but it still wasn’t common knowledge. Or even uncommon knowledge.
With the Borg sphere in range, it’s weapons will not be back online for 72 hours. The captain wants the heist practicing and Seven continues going through her parents’ records. The Borg Queen, however, knows that Seven of Nine is out there.
This was originally done as a feature length episode, but is more commonly shown in two parts, with the story continuing in the next episode, “Dark Frontier, Part II”.