Portrayed by Sigourney Weaver in the first and second movies, Dana Barrett was a single cellist living at 550 Central Park West (55 Central Park West), a haunted apartment building which would become the gateway for the apocalyptic deity Gozer the Gozerian. Dana is singled out early for unwelcome paranormal attention by Gozer's minions, and seeks the help of the Ghostbusters after seeing their advertisement on television. She is possessed by the demon Zuul, Gatekeeper of Gozer, who, along with Keymaster Vinz Clortho, opens the interdimensional gate to summon Gozer to Earth in the first film. She promptly attracts the romantic attention of Peter Venkman, whose flippant behavior causes her to doubt her decision to seek aid from the Ghostbusters.
In the sequel five years later, Dana is a divorced mother of an eight-month-old boy named [[Oscar (Ghostbusters)|Oscar; Venkman is neither her former husband nor Oscar's father. Dana was then working as a restorationist for the fictitious Manhattan Museum of Art. It is here that she (and later Baby Oscar) come to the attention of the evil Prince Vigo the Carpathian, whose malevolent spirit inhabits his massive self portrait. When Dana and Baby Oscar become the target of Vigo's plot, the Ghostbusters re-enter her life to save her, Baby Oscar, and the world once again.
Dana was also a neighbor of Louis Tully at 550 Central Park West in the first movie. The two remained acquainted, then became friends. Louis and Janine Melnitz baby-sat Oscar (and themselves became a romantic item) during the second film.
Weaver confirmed in June 2019 that she will reprise her role as Barrett in Ghostbusters: Afterlife (2021). Dana is the only character that didn't appear in The Real Ghostbusters and Ghostbusters: The Video Game.