This isn’t my vision of the future.
— Tom (William Fichtner), “The Fittest”

Christine (Elisabeth Moss) is one scary alien. Or wait. Not quite an alien. “Hybrid” is the going term, deployed by Sheriff Tom Underlay (William Fichtner) and them to ease the abject terror inspired by the very idea of human bodies being subsumed — or “changed” — by the lights on the water in Homestead, Florida.

Christine has emerged as the scariest exemplar of the change, if only because she appears so able to abide and inflict on others its subtle cruelty. That, and, she seems quite predisposed to pregnancy, a specific bodily change that she approaches as a nuisance and a threat to her sense of self-control. This time, already looking ready to give birth just weeks after becoming pregnant, she’s looking for a way to end it, dragging along latest boyfriend/fellow hybrid Derek (Michael Mitchell), because, in essence, she feels she must. In “The Fittest,” tonight’s episode, she complains about her current condition: “I didn’t need to be pregnant again,” she moans to Derek, as they putter along on a stolen skiff, looking for shelter along the watery coast. Derek affects concern, or maybe even really feels it, as if imagining that what she’s carrying is in fact a child.

Christine appears incapable of loyalty, sincerity or even basic affection, and so she presses on, using Derek, Tom, or whomever else crawls her way in order to achieve her own as yet unknown but nefarious-seeming ends. Christine’s efforts to keep hold of her own destiny (that is, not to be the mother of an alien future, or perhaps to be that future herself) makes her especially dangerous, in part because she’s unpredictable, in part because the camera tends to frame her from low angles and up close so that her pale countenance looms spookily, and in part because she’s damn ruthless. In this, she’s quite unlike other girls in Shaun Cassidy’s increasingly eerie series, which follows the folks of Homestead as they try to make sense of those lights and to rebuild their town after last year’s Hurricane Eve.

As the storm’s name suggests, the lights on the water herald a new beginning for these humans, many of them made slightly less puny or at least a bit scarier since their exposure. While Christine’s maternal body turns digitally veiny, glowy, and ominously throbbing (like John Hurt’s in Alien), other women have thus far remained mostly humanish: Christine seems set against intrepid reporter Larkin (Lisa Sheridan), married to Everglades park ranger Russell (Eddie Cibrian) and Russell’s ex, the pale blond doctor Mariel (Kari Matchett), both of whom struggle mightily and weekly with the fact of Mariel’s change and, to a lesser extent, Larkin’s impulse to uncover the “truth” of what happened.

The series begins with a kind of Invasion of the Body Snatchers notion: exposed to the lights, human bodies are exchanged (maybe replaced, maybe altered, maybe in perpetual mutation), which means that some of them spend a good deal of time and energy pondering what it means to be themselves, to assume fixed identities, to adapt to changes that undermine such presumption. The series alternates among the principals’ perspectives, imaging their fears in classic slow pans, internal frames, and deep shadows: even when the sun is out, this Florida town is dark.

In Fichtner’s persistently brilliant portrayal, Tom grapples with these questions while also serving as the hybrid community’s leader, sometimes imperturbably messianic (“The first few days are the hardest,” he tells Mariel on introducing her to the change he helped to visit on her), at others, head cocked, self-reflective and philosophical. Even as Russell remains righteously skeptical of Tom’s many maneuvers, he wants to believe that Mariel’s change is not all terrible, that she remains the caring and selfless mother of their two children — adolescent Jesse (Evan Peters) and precocious Rose (Ariel Gade), as well as Tom’s change-resistant daughter Kira (Alexis Dziena). As much as the kids take up much of the adults’ energies — as the parents and Larkin (also pregnant) insistently protect, indoctrinate, use, and love them — they’re also allowed their own spaces, distrustful of their guardians, developing their own desires. As the series focuses on Tom-and-them’s labors to manage the future, it also suggests that the kids have some ideas of their own.

The most obvious point of entry for viewers is Russell, a typically handsome Dean-Cainish sort who means to keep the community safe from the aliens he and Larkin’s brother Dave (Tyler Labine) discovered during Invasion‘s early days. In “The Fittest,” Russell must throw in with Tom — whom he distrusts absolutely — in order to track that daunting Christine. The men’s trek through the Everglades has Russell clenching his square jaw and Tom looking askance, neither imagining the other is his friend, and each seeking his own end in the excursion: Tom means to keep the hybrid community secret (the “scandal” would only ruin Russell’s kids’ lives, he insists), and Russell wants to hunt down the wretched killer Christine.

Their night’s adventure — which begins with Christine’s brutal bonking of Russell’s deputy Mona (excellent Aisha Hinds) — leaves Larkin and Mariel, the designated “moms” (and Dave, the “soft” boy), to explain the concept of hybridity to the kids. Jesse is especially unhappy to hear about it (though he anticipates the sit-down is about another sort of trauma: “Are you getting divorced again?” he asks Mariel, eyes set to roll). The men, meanwhile, encounter their own difficulties, namely, a group of migrant workers, starving, afraid, hiding after the storm. The chatty one, Omar (Jesus Mayorga), lets on that there’s a second group, who emerge from the water with fish on sticks, an image so spectral and odious that it makes the usual immigration anxieties look silly.

As this scene is quite gorgeous in its repetitive display of the fish, the men’s faces, the watery depths that nurture, hide, and define them, it also lays out yet another contemplation of self-ness and otherness. It’s in the consideration of race and race differences, the ways that categories of race, homeland, and family dictate your senses of self and security, that Invasion has emerged in its first season as one of television’s most insightful terrorism-scare shows. While the actionated spy and policing stories are more explicit in their treatments of these concerns, Invasion makes its scares visceral, intellectual, and ongoing. The questions it raises can’t be solved by incarceration, violence, and technology. The fact that the “military,” represented in part by Larkin’s source Vince (Matt Ross), is keeping warehouses stocked with containers and corpses hardly makes anyone feel more secure.

Indeed, the military, the “government,” and the local religious institutions all look to be part of the problem, not any sort of solution. This leaves individuals to their own devices, but without full comprehension of the risks and stakes, Russell can only bumble. “Survival’s what it’s all about,” instructs Tom, even as the episode suggests the “fittest” may not be those you expect. As competition develops among those seeking to survive, as violence and murder (however you define it) appear to be the only means to survival, Invasion looks to be less about humans reasserting their identities than about humans reconfiguring. Whether this constitutes survival is unclear.