Star Trek: Deep Space Nine
In my opinion, this is the best Trek there is, so let me fill you in.
Deep Space Nine is the new Starfleet designation for a space station built by the Cardassians and orbiting Bajor. The Cardassians, you see, had been brutally occupying Bajor for several decades. But the Bajorans fought back and in the end, the got the Federation to help them. The Cardassians were ousted and the Federation stepped in to help rebuild Bajor. The Federation would administer the now Bajoran space station.
Commander Bejamin Sisko was sent to take command. He wasn't too happy about it. Deep Space Nine was not a plum assignment. It was backwater, out on the frontier. And only three years before, he'd watched his wife die during a battle with the Borg at Wolf 359. Now, he had a son to raise alone.
Major Kira Nerys, the Bajoran liaison officer, and Sisko's new First Officer, was a former resistance fighter, tough and opinionated. She didn't trust the Federation, or the Bajoran Provisional Government for that matter. And she wasn't afraid to let anyone know it either.
Joining the crew from the Enterprise-D, Miles O'Brien was promoted to Chief of Operations and given charge of repairing the station. The Cardassians had not left quietly. They'd trashed the place. So the chief had his work cut out for him.
The Chief of Security also wears a Bajoran uniform. But Odo isn't Bajoran. He was a changeling, a shape-shifter whose natural state is a gelatinous substance. He was discovered the Denorius Belt and "raised" by a Bajoran scientist. He served as head of security when the station was under Cardassian control. He is respected by Bajorans because he was seen as impartial and interested in justice rather than oppression.
Lt. Jadzia Dax joined the station's crew as Science Officer a short time later. She had known Commander Sisko previously, in her previous host Curzon. Jadzia is a joined Trill, the seventh host of Dax, a non-humanoid symbiont. This makes Lt. Dax the oldest and youngest member of the senior staff. Jadzia was only 27 when she joined the crew, but Dax was well over 300. She married Worf at the beginning of the sixth season but was killed by a pagh wraith at the end of the season. Dax, the symbiont, was saved, though Jadzia perished.
Doctor Julian Bashir is the station's Chief Medical Officer. Young and somewhat naïve, Bashir had just graduated from Starfleet Medical, second in his class. He chose Deep Space Nine for the adventure of "frontier medicine." His seeming arrogance kept him on the bad side of several members of the crew, but things have come a long way in the last six years. . .
For starters, a stable wormhole was found nearby, the Celestial Temple of Bajoran religion, where the Prophets live. The wormhole leads to the Gamma Quadrant, an area that would take 70 years to reach at maximum warp. The Cardassians and the Bajorans sign a treaty--after much negotiation--and become allies with the Bajorans. Odo finds more of his people, changelings, in the Gamma Quadrant. Unfortunately, they are the founders of the Dominion. The changelings rule over many races, including the Vorta and Jem'Hadar, genetically engineered soldiers. The USS Defiant was added to the station. A warship prototype designed to fight the Borg, the Defiant is a tough little vessel without all the frills of the larger starships. The Klingons declare war, thinking Cardassia to be under the control of changelings and hoping for glory in battle. But it is revealed that a changeling, impersonating the Klingon General Martok, instigated the whole war to divide and weaken the alliances of the Federation. By this time, Lt. Commander Worf had joined the crew after the demise of the Enterprise-D (in Star Trek: Generations). Cardassians, now under Gul Dukat (former commander of Deep Space Nine) broken and weakened by the Klingon invasion joined forces with the Dominion, foreshadowing an all-out invasion of the Alpha Quadrant by foes from beyond the wormhole. And now, in the seventh season, the Alpha Quadrant faces war. The Klingons are again allies of the Federation and the Dominion was winning--for the time being. . . .
And Dax is back! In the form of Ezri Dax, a young Trill who never planned on being joined. An assistant counselor on the USS Destiny, she is offered a promotion and a transfer to DS9. Now a Lieutenant, she's the station's new counselor. She's got that to get used to, but also the new sensation of having eight other lifetimes worth of memories besides her own. Gul Dukat went off the deep end and Damar took over as the leader of the Cardassians.
Deep Space Nine ended its run a few years ago, with the Federation winning the war, naturally. Damar decided he didn't like the Dominion after all and led a rebellion with the help of Kira and Garak. Captain Sisko defeated Gul Dukat, who had thrown his lot in with the Pah Wraiths. Sisko is now with the Prophets in the Celestial Temple. Worf went to the Klingon homeworld as a Federation Ambassador, and Chief O'Brien went to Earth to teach at the Academy. Garak stayed on Cardassia to rebuild after the near genocide of the race by the Dominion. Kira was put in command of Deep Space Nine. The series now lives on in print as PocketBooks has decided to carry on the show. (See my book recommendations page for more information.)
That's long enough, I think. I hope I've interested you in the show. You'll find links below to sites where you can find out more about DS9 and the cast.