Meanwhile, on Centauri Prime: I wonder whether Londo would have left Morden alive (just forcibly removed from the planet) if not for the Adira revelation and am still not sure. He's certainly ruthless enough to regard killing Morden as the quicker resolution, and he's not exactly fond of him before that already, but otoh, he's not a gratitious killer, and just sitting Morden in a shuttle with armed guards would have done the trick. After being told about Adira, though, that definitely isn't a question any more, and Vir gets his wish. It's the one time we see Morden entirely lose his cool, and the second time (after And the rock cries out, no hiding place) we see Londo in cold calculating mode; it's also a scene rich in tragic irony, as Londo getting the better of the Shadows and Morden both is what ultimately condemms him to the Keeper. (Morden is the obvious candidate for "the one who is already dead", and I think londonkds is right - if Londo had gotten rid of the Shadows but kept Morden alive, Morden would have spilled the beans about the Drakh out of sheer indignation of being left behind when the Shadows left with the Vorlons.)

Sidenote: it's also the one death we see Vir not only not regret but be satisfied by, which I find fascinating, because objectively speaking, Morden isn't a monster the way Cartagia was. It probably comes down to Vir hating Morden for Londo's trip to the dark side, which isn't rational (Morden might have provided the opportunity, but Londo made the choices), but very psychologically plausible.

Speaking of death, and Vir: Londo asking Vir to kill him when the Vorlons show up is another of those heart-stopping scenes, because of what it says about them both. Both that Londo doesn't hesitate to offer his life for his world and that he asks this of Vir and trusts Vir would do it, despite this being the most horrible thing anyone could ask of Vir.

Lastly: loved the hug between them at the end, of course. Awww, Vir and Londo.