Although Jeri Ryan's ex-Borg drone Seven of Nine spent only four years on the USS Voyager, the rich history of Star Trek: Voyager's breakout character was revealed through flashbacks and dialogue.

By the time the fourth season arrived, Voyager needed some fresh blood in the cast. Lien departed the series, and in her place, Jeri Ryan was cast as the Borg known as Seven of Nine. Ryan became ...