The most brutal deaths actually took place in a hotel room in the first episode last week, and the execution of this family - father, mother, and daughter - provides a wake-up call not only for the Jennings but the audience. The slain family is almost in every respect an alternate of the Jennings - Soviet spies in Washington, with a real son (who is not killed, because he's out of the room) and a real daughter, to cement their cover. Their killer - who is still not known - could have done the same to the Jennings, who realize now that they wrongly assumed that, whatever might happen to the two of them, their kids would at least be physically safe.
One difference, of course, between the slain couple and the Jennings is that the Jennings are likely at least a little smarter, because they have so far managed not to get killed, though they have had some close calls. But this difference could be erased at any time, and Phillip's involvement of Henry in the hand-off, against his better judgement and at the slain father's behest, provides palpable evidence of just how close not only he and Elizabeth but their kids are to the razor's edge.
The killings in the hotel room and the vulnerability of the Jennings kids sets up the whole second season very nicely - that is, in a nice harrowing way. The kids are the essential illogical of these spies, so deep undercover that they have an actual family. As the psychological William James pointed out back in the 19th century, sometimes going through a function or activity engenders very real feelings which are usually thought to lead to the activity in the first place. It was clear all last year that, although the Jennings may have been pretending - a little - to truly love one another - there was no pretense at all regarding their kids. The Jennings love their kids as would any other couple.
And yet ... would any other couple allow their kids to be in such constant danger? This is the paradox of the perfect spy cover, which, if too perfect, tends to undermine itself.
This, in addition to the other lies and sex and life-and-death situations, is what makes The Americans such top-notch entertainment.
See also The Americans: True and Deep ... The Americans 1.4: Preventing World War III ... The Americans 1.11: Elizabeth's Evolution ... The Americans Season 1 Finale: Excellent with One Exception
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