Cassie Sullivan is a sixteen-year-old girl. That's hard. She's a sixteen-year-old girl that happens to be an orphan. That's harder. She's a sixteen-year-old girl that happens to be an orphan, and happens to be falling in love with an alien. Also: hard.
She's a (deep breath) sixteen-year-old girl that happens to be an orphan, and happens to be falling in love with an alien… and happens to be living in a post-apocalyptic world. To paraphrase Beyoncé, she's a survivor; she's gonna make it.
(At least for now—this book is the first of a three-part series, after all.)
Cassie's everything you'd expect from someone who has managed to live through an alien invasion. She's smart, athletic, determined, and practical. She's a little shell-shocked and a little depressed. She also has an assault rifle (and knows how to use it).
But she also has an extremely devoted alien boyfriend, which is fortunate since she's on a suicidal mission to rescue her baby brother from the clutches are far less devoted alien captors.
Cassie, though, wasn't always an odd mash-up of heroic abilities. She didn't always have the stamina of John McClane, the tenacity of Ellen Louise Ripley, and the scrappiness of The Force Awakens' Rey.
She was once a normal kid, with normal problems.
And that means that this novel deals with two Cassies, the pre-apocalypse Cassie and the post-apocalypse Cassie. We'll call them "Old Cassie" and "New Cassie" for short.
Old Cassie had an ordinary life, a family, a best friend named Lizbeth, and a major crush on Ben Parish. New Cassie has the aforementioned rifle and alien sweetie-pie. Things change, eh?
Thinking about the Old Cassie is a source of pain for New Cassie… and not just because Old Cassie had access to things like, say, electricity and metropolises that weren't filled with corpses. She tells us:
I'm talking about the Cassie I was before the Arrival…. … I'm probably crazy by that Cassie's standards. And she sure is crazy by mine […] I wonder what that Cassie would think of me. The Cassie who kills. (2.19-2.24)
See, New Cassie is a murderer. We learn that at the beginning of the book, when she kills a soldier during a routine water run. She couldn't know for sure if he was alien or human, so she did what she had to do. The world that New Cassie lives in is dog-eat-dog, or human-shoot-alien, or even (gulp) human-shoot-human.
Basically—as Evan sees it—Cassie did what Cassie had to do to survive:
Fear didn't paralyze Cassie Sullivan, like it did some humans. Fear crystallized her reason, hardened her will, clarified her options. (31.8)
Not that this kind of "You're okay!" pep talk cheers up Cassie all that much. After all, she shot a dude. And that memory haunts her.
But in our book (as well as in the book called The 5th Wave) that haunted-ness is a good thing. It means Cassie has a conscience.
And it's not only that Cassie is remorseful. She's also scared, angry, mopey, and tentatively hopeful. The alien invasion may have wiped out most of the earth, but it didn't turn Cassie into a robotic ice queen. She's a bundle of human emotions—Evan describes her as "terrified one moment, defiant the next." (31.10)—and those human emotions roiling inside her make sure that she keeps on keepin' on.
But we don't want to give you the impression that Cassie is a Gloomy Gus. She's not—she retained a bunch of the sunnier personality traits that defined her from before the arrival of The Others.
One is her sense of humor. She describes sarcasm as her "normal mode of communication" (33.43). (Can we be best friends, Cassie?)
And, over the course of the book, she gets in a few sick burns to break the tension of heavy moments. As she says goodbye to Evan—on her way to a near-certain death—Cassie tells him:
"By the way, somebody should say this: You look ridiculous in those pants." (73.14)
Post-apocalyptic pro-tip: never let the presence of body-snatching aliens interfere with your steez. The eradication of millions of humans shouldn't get between you and some well-tailored Levis.
Another characteristic Cassie was probably born with is good intuition—although we're betting constant danger probably honed that intuition a tad. In a world where logic has gone haywire, sometimes it pays to go with your gut.
Cassie's gut is pretty good, although she doesn't always listen to it. From early on in her association with Evan, she doubts his identity. She thinks:
Who is this guy? All of a sudden I've got a bad case of the jitters. Something is seriously wrong here. (36.105)
She ignores her intuition, though, because of one more crucial piece of her personality: Cassie's always crushing on guys. Hard.
That's right. Cassie is a teensy bit boy crazy. (In other words, she's your average straight female sixteen-year-old. Or twenty-year-old. Or thirty-year-old.)
Before the world ended, she was obsessed with Ben Parish, star quarterback and high school heartthrob. He was a hottie with a body, and a charming guy to boot. Who doesn't love a guy who's all about spending quality time with his siblings? It's adorable.
Knee-deep in the alien apocalypse, though, she falls for Evan Walker. He's handsome. He's caring. He tells it like he sees it. And—oh, yeah—he's an alien in a human body. Sorting through all those feelings becomes complicated, especially after Evan reveals his true identity.
On top of dodging alien attacks, rescuing her brother, and generally trying to survive, Cassie's mixed up and deeply self-conscious about her budding romantic relationship with Evan. Her concerns about sex seem almost equally important to her survival. When she's lying with him, she thinks:
What did he think about my body? What did I think about my body? Does God really care about promises? Do I really care about God? (34.49)
The questions mix together—being a human girl in love with an alien during the apocalypse will make you all sorts of mixed-up.
Even before, back in the days when she was Old Cassie, our heroine was never really comfortable dealing with this stuff. She says:
I had no problem with talking about sex. My problem was talking about sex as it related to me. (6.47)
New Cassie remains so insecure that she tells Evan, who's more experienced, that she used to date Ben Parish. (You wish, girl.) Cassie's not sure of her future, or of herself. When Evan tells her she's really pretty, she says:
"That's a good one. I don't know if it's true, but it's good." (53.60)
Again: all of this sounds pretty familiar. (The teenaged insecurity part, not the in-love-with-an-alien part.)
But there's one thing Cassie is sure of: that she's going to find Sammy, or die trying. She tells Evan,
"I won't give up until I do." (36.38)
And she isn't kidding. When it comes to finding and protecting her lil' bro, Cassie's tough as nails. We just wish that she could train that sharp focus on realizing how awesome she is… but you have to prioritize during a post-apocalyptic scenario, and we think Cassie's priorities are 100% on the money.