This ep introduces both Fred and Lucia and I can't help but think of the contrast between these two and the two Philip and Elizabeth work with in S5. These two are both so immediately interesting. Granted, they're also both spies so they're interacting with them in a very different way.
Lucia is the first of Elizabeth's younger (unlike Gregory) protegees. Their first scene together is great. You can see how Lucia immediately would look up to her but also want to prove herself to her and feel awkward about thinking Elizabeth didn't think she was good enough. Elizabeth goes immediately into teaching mode, refusing to come out of the shadows until Lucia gives her the exact right code words and giving he straightforward advice for the future, then adding at the end admiration for the work Lucia is doing and her country. You can definitely see Elizabeth being a good teacher here, with a different style to Philip, whom we'll later see teaching Paige to drive. It's hard to not not see every interaction like this with Elizabeth and compare it to her training with Paige, who so clearly lacks any real motivation or understanding of what she's doing, and it's reflected in her performance, and who Elizabeth passes anyway. (Elizabeth would have totally accepted the "close enough" password from Paige.) In some ways she's as cut off from Paige as she is from Henry, but tells herself it's worth it to hear Paige compliment her.
Meanwhile, Philip has a really fun interaction with Fred. He gets knocked out by a booby trap and wakes up about to be killed by him (or at least Fred thinks he should kill him). Then Philip Sherlocks the hell out of the scene, using all the little things he noticed in the apartment to appeal correctly to Fred. It's a nice parallel to Elizabeth's scene with Lucia because they're somewhat similar, but also not the same at all. It makes me wonder how Elizabeth would have handled the same scene. Philip's also in a more exposed position since Emmett saw him with Henry, who Fred correctly assumes is his son. This is the first (and maybe only, though I think there might be one more?) scene where Philip seems to hint at a close relationship with Emmett, one which seems to have truth to it even if he's deploying it to manipulate Fred. (He tells him Emmett didn't trust many people so if he told Fred about his family he must think highly of him.) It's mostly the delivery that makes it seem like it comes from truth.
I also think there's truth in Philip agreeing with Fred about a life where you don't really do anything--the kind of life he's trying to embrace in S6. It's not really who he is, and I think that's mean to be reflected in Henry once he starts getting motivated as well.
Basically, these two are both well-created to set P&E on their separate journeys. Lucia ultimately becomes about sacrificing the person for the Cause while Fred from the start clearly needs Philip to integrate himself more, asking about his real life. (Funny when Fred asks what "Paul's" real name was Philip says Emmett, which would have been the name he had in the paper and is the only name Philip knew, but is not his real name. I've always liked how the show often showed that characters in Russia by contrast used the real Russian names to refer to the person).
Henry in this ep continues to show how his interactions tend to have to be on his terms because he's hard to pin down. Elizabeth is playing a board game with the kids (there's references to family games elsewhere to, and this is the type of thing people tend to insist don't happen in this family) and Henry says he'd rather watch TV, which Paige says he always does when he's losing. (Seriously, Paige rarely has any interaction with Henry where she isn't being critical or condescending.) Then when Elizabeth takes them to the movies and begs off at the last second, Henry's clearly disappointed she's not going to watch the movie with them. I know many only see the side of Henry being neglected--but I always imagine him kind of regretting being so much that way. Although he does also ask if he could help out at the Travel Agency in response to Philip's story about difficult competition--another little reflection of Henry in S6 when he offers to hook Philip up with someone who'll give him advice.
Elizabeth's behavior maybe is what motivates Paige to go ahead and track down "Aunt Ruth's" address since Elizabeth does pretty obviously suddenly decide to go to a movie--any movie--right after she gets a phone call.
This ep is the first time Martha suggests buying her gun, the one that never goes off. Philip manages to talk her out of potentially switching FBI departments. He says she would be happier doing things that matter (as if equal opportunity employment doesn't), which is ironic given that ultimately Martha will choose to commit treason for Clark. Iow, it's him who matters and since he's the one who claims to be so focused on protecting America, his suggestion that she wants the same thing is probably all tied up in her wanting him to see her that way too. Not that there isn't any truth to it, but it's really not her diving motivation, clearly. She doesn't get into spying because she feels like she's helping her country, but because she's helping Clark.
Nina, meanwhile, is in the uncomfortable position of having to deliver explicit reports about sex with Stan to Arkady in person, and that scene is sandwiched between a scene of Philip talking to Elizabeth on the phone and Philip talking to Martha and begging off going to see her in order to be home with an obviously nervous Elizabeth.
It's interesting watching this ep given where Elizabeth is in S6 because here she's genuinely worried about the kids, saying it never before occurred to her they could be in danger. At this point she's still keeping the cover life/kids and her work completely separate. Philip still feels terrible about just using Henry as a prop to identify himself to Fred and when Elizabeth reassures him he didn't have a choice, he says he did. In the last ep there's a similar convo. This time it's Elizabeth who "can't believe" she did something--in this case, killed a KGB officer. Philip gives her the same reassurance, saying something like "What were you supposed to do?" The implication again, there, is that she did have a choice and this was the choice she made--just as Philip chose to do the job for Emmett.
I guess that's why it'll start to create so much trouble when the Centre mixes the two worlds up. Then Elizabeth starts trying to have it both ways: hold onto Paige using the Centre and be loyal to the Centre by using Paige. And it leads her into this numb dreamworld where she again pretends that Henry and Paige couldn't be in any danger, even while she ignores not only the danger she's putting Paige in but Paige's being uniquely incapable of dealing with it.
Oh, and this ep is also the one with the convo that mirrors the very last one when Elizabeth asks how she and Philip are supposed to live "like this"--meaning knowing the kids could be in danger and Philip replies "We'll get used to it." Btw, Philip also looks at her in something like surprise when she says she never thought the kids could be in danger. I wonder if he's surprised that she now thinks they are, or that he's shocked it never occurred to her before. The latter seems far more likely, given Philip.