This episode manages to be a standalone monster of the week episode, while simultaneously digging deep into themes that play into the wider arc. There's also a completely baffling encounter, that only makes sense if you look at this episode in terms of the overarching plot and the show's need to be flexible about external factors.
We open with Ambassador Kosh contracting telepath Talia Winters for a job, and Ambassador G'Kar's aide Na'Toth trying to kill a visitor to the station with her bare hands.
The visitor is a trader going by the name of Gyla Lobos, travelling with Minbari ID, clothes, and ship, although she's not Minbari. According to Na'Toth the visitor is Deathwalker, a Dilgar war criminal notorious for her experiments on prisoners - including Na'Toth's grandfather. The problem is, the Dilgar have been extinct for thirty years and Deathwalker herself should be much older.
G'Kar persuades Sinclair to release Na'Toth into house arrest in his custody, where she tells him she's sworn a blood oath to kill Deathwalker. She's not pleased when he tells her to put it aside for the good of their people - the Narn government is trying to make a deal with Deathwalker for a discovery that will give them an advantage over their enemies. Na'Toth agrees to postpone her claim and G'Kar promises to help her fulfill the blood oath once they have what they want. However Deathwalker's price is Na'Toth's execution and G'Kar refuses, despite his previous words to Na'Toth about the need to sacrifice for the greater good. It's a lovely piece of characterisation that even G'Kar, previously depicted as ruthless, has a line he won't cross.
The Narn aren't the only ones interested in Deathwalker's secrets. Sinclair receives a call from Senator Hidoshi back on Earth instructing him to send Deathwalker once she's recovered, and Ambassador Mollari stops Sinclair in the corridor to ask if the rumour of Deathwalker being in custody is true. The rumours spread even further once G'Kar warns the other ambassadors Deathwalker is on the station, to prevent her from leaving.
Deathwalker reveals to Sinclair that she is who Na'Toth claims. The reason she looks young age is an anti-aging and disease serum she's developed, which she intends to share with the whole galaxy - immortality for all. She claims to have been sheltered by a Minbari faction called the Wind Swords, and comments they're right to fear Sinclair. This, of course, is a nod to the previous episode and the revelation that during the Earth-Minbari War he was captured and interrogated by the Minbari shortly before they surrendered, before being released with no memory of the encounter. It's also interesting that literally the only interaction Sinclair and Deathwalker have had at this point is Sinclair walking into Medlab, introducing himself, and asking Doctor Franklin to give them a moment. "You know the way of command" she tells him approvingly, but it's honestly difficult to imagine her phrasing her orders as questions. Her impression appears to be based on the fact Sinclair does exactly that, with the expectation of being obeyed, and Franklin does as he's told. There's very little of Franklin in this episode, but there's a lovely piece of characterisation here even though he doesn't say a word. When Sinclair arrives, Franklin is between Deathwalker and the door, clearly unhappy about being near her and just as clearly positioned to stop her leaving even though they both know he couldn't actually stop her.
As Sinclair prepares to ship Deathwalker off to Earth, the Ambassadors gang up on him and force a council meeting to decide what will be done with her - the League of Non-Aligned Worlds wants her to stand trial on Babylon 5. The problem is, they only get one vote between them. Sinclair votes with them (almost certainly not what Senator Hidoshi had in mind). The Vorlons, as always, abstain. The Centauri vote no and the Narn, after the trial being on Narn is refused, also vote no. Sinclair's plan hinged on the Minbari voting yes, but they don't. It's another nice characterisation note that it's Lennier who casts the vote as Delenn is away. He's obviously unhappy about doing it, but does as he's told and apologies to Sinclair after. He's also the one who admits the Wind Swords did harbour Deathwalker, and used her to create weapons to fight Earth with during the war, which the Minbari are now too ashamed to admit. It's almost certain Delenn would not have told Sinclair this, but Lennier doesn't appear to think twice and I'm not sure if this says more about him or his perception of Sinclair.
Vote defeated, they stick Deathwalker on a ship. This time a whole fleet of ships from the various League worlds arrives and threatens to attack the station. After a brief standoff, Sinclair tells the League ambassadors about the serum and proposes they send scientists to Earth to help with its development . When it's finished, they can have Deathwalker for trial - a more civilised version of what G'Kar promised Na'Toth. Deathwalker is scornful of the idea, saying the Earth Alliance won't let it stand. Her parting blow is to tell Sinclair that the key ingredient in her serum can't be made, it has to be harvested from other living beings. Watching the other races tear each other apart will be her legacy.
Then her ship leaves and the Vorlons blow it up.
Ambassador Kosh tells the rest they aren't ready for immortality, and glides away. While all this is going on Talia's having a very odd encounter, and really the only thing that connects the two storylines is that Kosh is in both.
It's established earlier in the season that Talia's job as a commercial telepath is to scan both parties during negotiations to ensure everyone's on the same page. Which is exactly what she does here, except that Kosh's associate Abbut has a completely blank mind, and the pair of them talk rubbish. Talia's confused and upset, since the constant scans are tiring and end in her having unpleasant flashbacks. The nonsense talk is amusing and adds some levity, but the whole thing would probably be a lot more interesting if it weren't for all the Deathwalker business going on. However, since the whole point is to put a gun in a drawer that's never used (more on that later), burying it in a plot that's more interesting was probably the best thing they could have done with it.
At the end of the negotiations, Abbut removes his hat to reveal a cybernetic brain and removes a data crystal which he hands to Kosh. When asked, Kosh tells Talia it contains "Reflection, surprise, terror. For the future." Talia takes her concerns to Sinclair and Garibaldi, and the latter tells her Abbut is a Vicker (VCR, an excellent pun that only works if you believe people will still know what that is in the 23rd century), part organic and part machine, used by aliens to record things. They can only guess why Kosh wanted to record Talia, but their guess is that it's because Vorlons don't trust telepaths. What might be the real reason becomes apparent later.
Despite not actually moving on the main arc, the episode manages to touch on the themes of immortality, whole races going extinct, the need to sacrifice for the greater good, and Sinclair's backstory with the Minbari. Because of this, unlike other less successful monster of the week episodes, it's difficult to see how this one could be removed and not leave a gaping hole