Turns out all Helix needed for a major rebound on Day 4 was to separate its heroes. The Jules-Alan-Sarah triangle had been chugging along without striking many sparks, but this episode breaks up the brain trust and starts to ferret out their secrets and, perhaps more surprisingly, their personalities. The pace of the show slows down in a sense, including the introduction of a few new characters as foils for the main trio, but that actually gives time to delve into their pasts and lets the audience start to feel a genuine stake in their survival.
The last episode was stingy with its secrets, but “Single Strand” both clarifies the scientific mystery—the virus serves to deliver a segment of DNA from host to host—and deepens it, because who (or what!?) created the virus, and the purpose of that DNA alteration, are unknown. Similarly, we get more solid information about Alan, Peter and Jules’ connection to the virus, but in a way that provokes still more questions about their place in Hatake’s grand plan.
Alan finally gets to have it out with Peter, but with Peter at death’s door, it’s a gentle confrontation. The emphasis on Alan and Peter’s rough childhood, which seemed forced in earlier episodes, looks to have a link to what’s happening in the lab. Peter says of their father, “Something about being trapped in this place, I see that bastard around every corner.” What exactly did their father do to them, and what does it have to do with Hatake bringing them there? Adding another level of intrigue is the suggestion that the compulsion to recall childhood may be a product of the virus itself, something it may in fact manipulate. Certainly there are parts of Peter’s confession that are for real, such as his affair with Jules going on for much longer than Alan realized (or probably really wanted to know). Absorbing that bombshell, Alan doesn’t latch onto Peter’s disclosure that Hatake was always much more interested in Jules than in him.
But we already knew Jules to be the linchpin of this whole thing. Casually consigned to death by her fellow Level R prisoners at the start of the episode, Jules catches sight in the hall of a figure in a peculiar hazmat suit with a coffee-can gas mask. When she chases the figure, it runs, then disappears. Soon after, along comes a vector ransacking cabinets, looking for whatever vectors look for when they can’t find raw living flesh, cheese in a can or whatever. As Jules flees, the mysterious figure jumps out to save her. The way this is all staged seems to confirm that the woman in the suit, called Jaye, is real, that Jules only thinks she hallucinated her the first time. But certain other aspects of Jaye—her oddly old-fashioned gear, the fact her name sounds like an initial for Jules’ own, her familiarity with the base that Jules may herself possess—imply that Jaye could be an incarnation of Jules herself. Jules’ discovery of her initials and favorite flowers carved into the wall with a child’s hand could be taken two ways—that she really had a past there, or the virus wants her to believe that she did. She might be uncovering a secret somebody wants hidden, or the virus may be leading her down the primrose path to some hellish trap.