A member of Species 8472 disguised as a Starfleet commander in a recreation of Starfleet Academy, who dated Chakotay before exposing him as human.
Valerie Archer is a member of Species 8472 who has been genetically altered to look human and assigned to a training ground built to resemble Starfleet Academy on Earth. In In the Flesh, Chakotay infiltrates the simulation and meets her, posing as a Starfleet officer, and the two arrange a date.
Archer secretly takes a sample of Chakotay's DNA, discovers that he is genuinely human and reports him, leading to his capture. The standoff that follows ends in negotiations between Janeway and the leader of the facility, who believed Starfleet was planning to invade fluidic space. The two sides eventually agree to a truce.