A scene in "War Without End", from the middle of the magical season 3:
The last minute or so of that episode..... OMG, OMG, OMG. Didn't see anything as powerful with such impact until the last minute or so of Doctor Who's "A Good Man Goes to War", where something important is revealed about River Song.
And in both cases, years of setting the foundation for that payoff. Note I'm being careful not to give away spoilers, but those who have not seen it but may eventually, may not want to read the next paragraphs as there are some clues and one distinctive event that occurred later.
Although, if Michael O'Hare had not left the show after season 1 (JMS revealed after his death that O'Hare had psychological health issues, until then it was thought for years that the studio forced him out), and had stayed on thru the series, the last episode of Babylon-5 might have been very different. Pretty much, the basic ending shown in War Without End would have been the end of the show, after B-5 had been destroyed, which would have been even more mind-blowing if it had played out that way.
One thing that supports that is how the Centauri seer's vision (her visions always came true) of B-5 being destroyed, ends up in the last episode as a very weak excuse of destroying an empty decomissioned B-5 on purpose so as "not to be a danger to ship navigation" (yeah, blow up a 5 mile long space station in a predictable orbit, to create a few million pieces of space junk to create a doughnut-shaped debris cloud around Epsilon-3, a ship navigation nightmare). JMS would not have planted such a powerful impending seed of destruction so early, only to have such a wimpy almost totally unimportant and frankly stupid result at the end (but he was obligated to show B-5 being destroyed to prove the vision as being true). There had to have been something way better that he had intended.
Below, a 1:45 clip from "Severed Dreams". Awesome scene with the line : "If you value your lives, be somewhere else"
- George Gassaway
[video=youtube;UYloWBP79ro]https://www.youtube.com/watch?v=UYloWBP79ro[/video]