DS9 is more character-focused and has longer story arcs than any Star Trek series before it (and after it until Disco). Unlike Disco, which is sheer melodrama, DS9 manages to simultaneously be fun and challenge viewers with dark and thought-provoking content.

After forming an attack plan on the Dominion, Sisko relinquishes command of the Defiant to Dax after accepting a promotion. On DS9, the resistance faces discovery when Odo links with another changeling.

Tahna Los, a former Bajoran terrorist during the Occupation, asks Sisko for asylum on DS9. Meanwhile, the station's last Cardassian inhabitant, Garak, possibly a former spy for the Cardassian government, proves an interesting mystery to Dr. Bashir.

When Dr. Bashir learns of the deadly disease Odo is infected with, he meets with resistance whilst trying to obtain Odo's medical records from Starfleet. Martok gets blindsided by Gowron when he arrives on DS9, announcing he has assumed command of the Klingon fleet.

Behind the Lines: Directed by LeVar Burton. With Avery Brooks, Rene Auberjonois, Michael Dorn, Terry Farrell. After forming an attack plan on the Dominion, Sisko relinquishes command of the Defiant to Dax after accepting a promotion. On DS9, the resistance faces discovery when Odo links with another changeling.

Terry Farrell. Actress: Star Trek: Deep Space Nine. Terry Farrell was born on November 19, 1963 in Cedar Rapids, Iowa. At age 15, she became a foreign exchange student to Mexico, and, from that experience, she decided she would like to live a more adventurous life in the big city.

By Inferno's Light: Directed by Les Landau. With Avery Brooks, Rene Auberjonois, Michael Dorn, Terry Farrell. The station readies for a Dominion attack. Worf and Garak meet some unexpected friends in a Dominion Prison camp.

The first officer aboard DS9 would have been Ro Laren, but she was replaced by Kira Nerys (Nana Visitor) because Michelle Forbes did not want to commit to a six-year contract working on DS9. Indeed, the reason the producers had decided …

Melora Pazlar, a new arrival on DS9 with a special gravity-based disability, finds an admirer in Bashir. Meanwhile, an old associate of Quark's comes to the station to kill the bartender.

When we finally have the explanation for the big mystery of Fenna's disappearances it feels very much like a quick tick in the box to remind everyone the writers haven't forgot DS9 is a sci-fi show.