The story of Stargate Atlantis follows the events of Stargate SG-1's seventh season finale episode "Lost City", in which the cast of that series discovered an Antarctic outpost created by the alien race known as the Ancients. In the pilot episode "Rising", Stargate Command sends an international team to investigate the outpost, where Dr. Daniel Jackson discovers the location of Atlantis, the legendary city created by the Ancients.Of course, those wacky Tyree of Stargate command can't resist but send an expedition right away to find out what's the deally-o with the lost city of the ancients. The problem is that because of the amount of power required to get there, it's a one way trip. Most of the first season is spent bitching about this... but in a "look at this tremendous sacrifice we've made that no one will ever know about" way. (This is an old writer's trick to elicit unearned sympathy from the reader/viewer... you want someone to feel sorry for your protagonists, strand them far from home with no hope of return. Now you too see the man behind the curtain.) One can just imagine how that briefing went...
Daniel Jackson: So, we've figured out how to get there. It will take a lot of power, but we can do it...
O'Neill: Okay, that's great... how do we get back?
Daniel: Not real sure on that part.
O'Neill: You said the same thing the first time we stepped through the Stargate. You know, back when I looked like Jeff Bridges?
Daniel: Well, we did get back.
O'Neill: I ain't going. Why don't we send that annoying civilian observer they saddled us with last season?
Daniel: Good idea. No sense in risking our lives on my half-thought out theory again.So our team, (led by former civilian observer to Stargate command Dr. Elizabeth Weir... seriously.) enters the Pegasus Galaxy and immediately finds out that the city has been abandoned, and that they don't have the power to return. The team is "Multi-cultural" in that it's supposed to be made up of people from exotic countries around the world like 'Canada', but it's really just a bunch of cookie cutter stereotypes. You've got the "strong yet feminine peacenik diplomat leader" (Dr. Weir), The "Tortured Military leader with the heart of gold" (Major John Sheppard), The "Bumbling and arrogant but brilliant scientist" (Dr. Rodney McKay.. a character whose most memorable trait was that he hit on Carter a few times back at the SGC) and the "alien chick who knows her way around the Galaxy so let's trust her now" (Tayla).
The rest of the expeditions is primarily made up of heavily accented actors playing nuanced parts like "soldier with guns", "medical doctor", and "second scientist in case the first one breaks".
Seriously... it's not till the second season that any of them really start to develop a personality.
So, the United Nations of Benetton ad that they've sent on this mission goes and wakes up an ancient enemy of the Ancients known as the Wraith. The Wraith are basically space vampires, only they don't sparkle or have that annoying weakness to sunlight. Seems that in the Pegasus galaxy the Wraith awaken every 1000 years or so, eat all the humans they can gorge themselves on, and then go back to sleep. Only the folks from Atlantis interrupted their nap (our bad), and now they're pissed.
I know I'm making it sound just awful, but the characters do come around to being likable by the end of the first season, and once contact is made with Earth again the series really finds it's legs. There is a lot of good in the series, and it was a really fun ride. By the time I got to the series finale, I was genuinely disappointed that it was over.
"The Seige"- The Wraith stage an all-out attack on Atlantis
"Runner"- introduces Ronin Dax, the teams token "alien dude that kicks ass"
"Progeny"- a race that appears to be the Ancients aren't quite what they seem
"First Strike"- a preemptive strike against an old foe has disastrous consequences
"Midway"- worth it if only to watch Ronin and Teal'c beating the piss out of each other while the Atlantis crew bets on them
"Enemy at the gate"- Atlantis is all that stand between the Wraith and Earth.