A Borg vinculum (never heard that term before - basically it is some sort of central computer core of a Borg cube) causes Seven to split into several different personalities. Instead of being humorless and distanced, Jeri Ryan can show her acting talent by impersonating a small child, a Klingon, a Ferengi, a Vulcan... but because those splits come quicker each time, there is a risk, that Seven may lose her own personality soon. The Voyager crew salvages the Vinculum and discover, that it has been infected by a virus. Since they are unable to destroy it and prevent Seven from splitting into other personalities, they search for the last species, that has been assimilated by this Borg vessel.
When they encounter this species, they admit that they have created this virus and intentiously infected the Borg to destroy them. They argue with Janeway to return them the Vinculum so the virus can spread to the next Borg cube but Janeway wants to first cure Seven before she hands over the thingy and even risks to be destroyed by the aliens.
The story and Jeri Ryan's performance are quite good in this episode, but still some twists don't make sense. For example when Tuvok tries to mind meld with Seven to prevent her from losing her own self. What we see then is a distorted metaphor of her mind where dozens of different species seem to be eager to throw Seven into a deep pit. Tuvok though doesn't really stop those guys, his mind meld is quite pointless. Seven survives not because of Tuvok but because the crew was able to sever the connection to the Vinculum before the other personalities overpowered her.
Also, Seven says, that it doesn't matter if they get distance to this computer core because it sends its messages in subspace and will reach her no matter what. But at the end, they hand this vinculum over to the alien species. Most likely they will activate it again. Their whole purpose has been, to lure other Borg cubes to it so it can spread its virus to them. Once they would activate it though, Seven should be affected right away again. But obviously the writers haven't thought about this loophole.
When they encounter this species, they admit that they have created this virus and intentiously infected the Borg to destroy them. They argue with Janeway to return them the Vinculum so the virus can spread to the next Borg cube but Janeway wants to first cure Seven before she hands over the thingy and even risks to be destroyed by the aliens.
The story and Jeri Ryan's performance are quite good in this episode, but still some twists don't make sense. For example when Tuvok tries to mind meld with Seven to prevent her from losing her own self. What we see then is a distorted metaphor of her mind where dozens of different species seem to be eager to throw Seven into a deep pit. Tuvok though doesn't really stop those guys, his mind meld is quite pointless. Seven survives not because of Tuvok but because the crew was able to sever the connection to the Vinculum before the other personalities overpowered her.
Also, Seven says, that it doesn't matter if they get distance to this computer core because it sends its messages in subspace and will reach her no matter what. But at the end, they hand this vinculum over to the alien species. Most likely they will activate it again. Their whole purpose has been, to lure other Borg cubes to it so it can spread its virus to them. Once they would activate it though, Seven should be affected right away again. But obviously the writers haven't thought about this loophole.