Following a transporter malfunction on beaming back the away team from a survey, a powerful Borg drone is born on Voyager - a fusion of Borg and 29th century technologies (from Seven's nanoprobes and the Doctor's mobile emitter) and human DNA (from Ensign Mulchaey). One, as the new drone designates itself, begins learning human values and adapting to life aboard Voyager. However, although his connection to the Borg Collective is dampened, unknown to anyone on Voyager One's cranial implants create a secondary transceiver to signal them. As a Borg sphere approaches, One steers it to destruction within the protonebula then sacrifices his life to prevent the same thing happening again.

Voyager near the protonebula

Borg tubules sprout from the Doctor's mobile emitter and start assimilating the LCARS control panel in the science lab

Paris, Torres, Seven and the Doctor have been on an astrological survey to explore a protonebula. One steers the Borg sphere which later threatens to its destruction within it.

Voyager's science lab is on Deck 8 Section 22. In this story it is assimilated by Borg technology and the control console transformed into a Borg maturation chamber. The science lab is also seen in several other episodes e.g. [#71 Day Of Honor].

Seven discovers the maturation chamber

Torres' bathroom is seen again in this episode. It is also seen, or parts of it, in [#97 Extreme Risk] and [#115 Juggernaut].

Torres' bathroom

Voyager's construction consists of duranium hull, plasma-based power distribution, tricylic life-support systems, and artificial gravity plating.

Engineering is on Deck 11 Section 32.

The warp core maximum output is 4,000 teradynes per second.

One helps increase the efficiency of the Bussard collectors.

One gives the crew the ability to remodulate the shields and enhances phasers in order to defend Voyager against the Borg.

The airponics bay is still in use, but with Kes' departure in [#70 The Gift] no one in particular has been established as her replacement for supervising it.

Janeway and Seven show One visual files of a Borg attack.

astrometrics lab: visual files

The Doctor brings a holo-imaging device to take photo snaps of the protonebula. This is the first time he is seen doing this hobby although in [#105 Latent Image] it will be established that he has been actively pursuing it for a while.

the Doctor with holo-imaging device

The Doctor's mobile emitter is embedded in One's cerebral cortex and has adapted to function as part of his nervous system controlling all autonomic functions. After One's suicide, the mobile emitter will be returned to the Doctor.

A class-2 shuttle is lost when it is caught in the gravimetric shear of a protonebula.

When the away team complains of the poor design of the class-2 shuttle, Seven suggests designing a new shuttle, which Torres believes to be a good idea. This will lead to the design and construction of the Delta Flyer in [#97 Extreme Risk].

Warp drive is taken out when the Borg invert Voyager's phaser beam with a feedback pulse. Kim reports shield strength is down to 29 per cent.

"Class-2 claustrophobia" is how Starfleet cadets used to refer to the shuttles, as they were fast and maneuverable, but not built for comfort. Starfleet Academy professors used to shoehorn half a dozen cadets into one of them for weeks at a time.