He’s wounded and bleeding in a shadowy corner of a convenience store, he’s asking for her help, and he’s pulling his hand from beneath his jacket - the hand holding the crucifix - when she shoots him. The crisis posed by Wounded Man with Crucifix is striking, of course, symbolic in every way possible. And being human means being her old self, the “totally normal high school girl” who played on the soccer team, had a best friend of color (Gabriela Lopez), and flirted with a football star named Ben (Nick Robertson). For Cassie now, post-alien invasion (yes, there is one, per the YA manual, killing humans means being not quite human.
It’s a big idea for a young adult story, and so the plot makes plain the difference between human and not human, even if it still fudges the less definable “ity” part. This young man appears in Cassie’s nightmare of a new life in order to lay down the Major Theme, namely, that she wants to recover her “humanity”. The present Cassie (Chloë Grace Moretz) has just killed someone (Matthew Zuk), identified only as “Wounded Man with Crucifix”.
“I miss the Cassie I was,” laments the Cassie that is at the start of The 5th Wave.