It is an important episode for the character "Seven", as she showed that she is determined to stay with Voyager as opposed to rejoining the Borg Collective.

A small team from Voyager, including Seven of Nine and the ship's holographic Doctor, are performing a survey of a proto-nebula on a shuttlecraft. When the nebula becomes unstable, the team is evacuated via transport to the ship, but a malfunction briefly merges their patterns together. The malfunction is corrected, and the team is safely transported aboard. The Doctor finds his mobile emitter is failing, and he is safely returned to sickbay while Lt Torres takes the emitter to the science lab to attempt repairs the next day. The crew is unaware that the emitter has gained some of Seven's Borg nanoprobes from the malfunctioning transporter, and it begins assimilating the equipment in the science lab.

Ensign Mulcahy enters the lab the next day, but is knocked unconscious when extraction tubes from the assimilated equipment strike him and take a tissue sample. Seven awakes from her regeneration cycle early and detects that her proximity transceiver has been activated; it happens again while she is in sickbay. The crew is soon aware of a large power draw from the lab, and discover that the nanoprobes have constructed a Borg maturation chamber, rapidly growing a Borg drone from the tissue sample. They determine that the components of the drone are based on the 29th century technology of the emitter, fused in the drone as part of its cerebral cortex; should the Borg of this timeline gain that information, the entire galaxy would be doomed. Captain Janeway orders Seven to disable the Borg transceiver in the drone, but, after struggling with an ethical choice, tells her to allow the drone to mature, hoping to make it understand humanity's individualism once it is out.

The drone (played by J. Paul Boehmer) soon leaves the maturation chamber, and though it immediately attempts to seek out the Borg collective, Seven attempts to convince the drone that he is an individual. She tries to use a direct neural link with the drone to provide it information, but the drone overpowers her control, and attempts to download all the information Seven knows before she manages to put a stop to it. Seven instead enables the drone's linguistic functions, allowing it to learn by language. Several of the crew help to provide the drone with useful information, purposely omitting information about the Borg collective, and soon the drone appears ready to adapt to being an individual, requesting that he be named "One". One recognizes that he is more advanced than any of the technology on Voyager and suspects that he was formed as a result of an accident.

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