Seven of Nine was played by Jeri Ryan for four Voyager seasons. The character was a part of the last four seasons which concluded in 2001 with its seventh season, and Seven was featured in many episodes despite coming later to the series. Seven was introduced in the second part of the episode "Scorpion '', the first episode of the fourth season. The character continued to appear throughout the series until the final episode, "Endgame ''. Stories related to her relationships with Captain Janeway and The Doctor appeared throughout the series.
star trek voyager 7 of 9 first episode
the first episode of the fourth season