One of Three was a freed Borg drone, like her siblings Two of Three and Three of Three, and served on the USS Voyeur. (VOY: "Author, Author", RIS Bouteina)
- In "Author, Author", the USS Voyeur, as well as its crew, was imaginary, but was real in RIS Bouteina.
She served as the security chief of the Voyeur before her captain and her XO were transferred to the USS Hercules. She then became the captain of the Voyeur. (RIS Bouteina: "Take Me Out to the Zoo")
Her real name is Sirena Seiffert. (RIS Bouteina: "Relief and Refuge")