TREKCORE > VOY > EPISODES > SURVIVAL INSTINCT > Synopsis

Thanks to StarTrek.com:

Voyager is docked at the Markonian Outpost Space Station. Captain Janeway announces to the crew that the doors have been opened for anyone to visit. Seven of Nine and Naomi Wildman go to lunch together in the Mess Hall where they are surrounded by numerous alien visitors.
A man approaches Seven of Nine and puts his briefcase-sized container on a table. When Seven of Nine notices the Borg equipment, she bolts up. Suddenly, Seven of Nine begins to experience memory flashbacks from her past as a Borg.

The items turn out to be Borg relays from Seven of Nine's original unimatrix. The man offers them to Seven of Nine, but when he speaks it seems that his words are not his own and are instead chosen for him. Seven of Nine accepts the Borg relays and she tells the man that Captain Janeway will compensate him. As the man walks away, he communicates telepathically with two others, telling them to prepare to penetrate Voyager's security systems.

Seven of Nine brings the Borg relays to Torres for her evaluation. Seven of Nine tells her how the items triggered visual images, sense memories, sounds and smells. Torres suggests that Seven of Nine was experiencing nostalgia when she first saw the relays. However, Seven of Nine insists that she isn't having any feelings whatsoever about the past. Seven of Nine leaves the relays for computer analysis. Just as she returns to her alcove to regenerate, the Borg relays begin to emit a soft beeping.

Next, three Borg (the first is the man who brought Seven of Nine the Borg relays) enter Seven of Nine's alcove. Two assimilation tubes appear from one of the Borg's arms and begin to penetrate Seven's neck. Seven of Nine unconsciously becomes aware of their presence and when she opens her eyes she begins to fight them. Suddenly, Tuvok and the Security team's phaser fire hits the three Borg and they crumple to the deck.

Seven identifies the three as Two of Nine, Three of Nine, and Four of Nine. They were all once members of the same unimatrix, but Seven of Nine has no idea why they were trying to access her memories. The three Borg tell Captain Janeway that their goal was to break their telepathic link and become individuals.

Apparently, Seven of Nine and the other three Borg were the only survivors of a vessel crash eight years earlier. However, when they were reassimilated into the Collective, the three were somehow linked together permanently. When the three finally escaped, they had their implants removed but they couldn't break the telepathic link between them. They were hoping that Seven of Nine remembered what happened to them.

Seven of Nine suggests linking her neurally to the three Borgs, in order for them to find the truth. Unfortunately, there is the possibility that she becomes trapped in the neural link. Despite the risks involved, Seven of Nine decides to go ahead. When Seven of Nine's neural link is connected to the Borgs, they discover that Seven of Nine was the one who reassimilated them.

The Doctor then breaks the neural link between Seven of Nine and the other three Borg. As a result of the process, the three Borg damage their brains which sends them into a comatose state. The Borg will only survive for a month unless they are reassimilated into the Collective.

Initially, Seven of Nine decides that their survival is the most important. However, after she talks with Chakotay, she decides that by removing their neural implants, they will be able to live as individuals for a short time. When the three wake up, they begin to make separate plans for their brief, yet individual futures.