"Survival Instinct" is the 122nd episode (the second episode of the sixth season) of the science fiction television series Star Trek: Voyager. In this episode, Seven of Nine encounters three Borg with whom she was previously linked.

Voyager is docked at the Markonian Outpost Space Station, which has welcomed the wayward ship with open diplomatic arms, allowing the free exchange of gifts and ideas. While meeting several representatives of various species in the mess hall, a man approaches Seven of Nine, revealing a container of several Borg implants as a gift. The sight stuns Seven and brings back memories from her past as a Borg. As the man walks away, it is revealed that he is in telepathic-like communication with two other guests aboard Voyager, preparing with them to penetrate the ship's security systems.

With B'Elanna Torres's help, Seven identifies the implants as part of her own unimatrix but denies having experienced any feelings at their sight. After returning to her Borg alcove to regenerate, the man and his two accomplices enter the cargo bay, revealing themselves as former Borg drones. They attempt to inject Seven with nanoprobes but she detects their presence, stops the attack, and alerts security. The three are subdued and taken to sick bay. The Doctor determines that while they are former Borg, the process to remove their Borg implants was imperfect which left the three with a shared mental connection. When they awake, the three affirm their condition, stating that they were also part of Seven's unimatrix, and want to bring her into that connection to learn what happened some years ago when their Borg scout ship crashed on an uninhabited planet. Seven herself cannot recall the event, but agrees to link to the others temporarily to attempt to uncover it.

Told in flashbacks through the episode, after the crash, the four survivors - no longer in contact with the Borg collective - constructed a communication array to contact the Borg for rescue. As they waited, the other three began to feel some aspects of individuality, while Seven fought against it. When they realized the Borg were approaching, the other three attempted to flee, but Seven followed them and re-injected each with nanoprobes, neutralizing their individualistic tendencies and re-assimilating them to the collective.

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