This week's episode eight was appropriately titled "Are We There Yet?" With only four episodes left in the series, we can't be the only viewers anxious to know how the series will end. And it could also be a wink and nod from the producers who know who the real Brain Surgeon is; perhaps they're asking if we're there yet in catching up (yes, actually, we are). The title is also used in the classic sense of a little kid asking his parents if they've arrived at their destination. In this case, Zach Hamilton is the kid.

Before we go any further, we just want to point out how we totally called it. Way back when episode one of this season aired, we said, "But is she more than just a nosy scientist? Although we want to say it looks like Vogel will end up being the Brain Surgeon, it's too easy, so it can't be -- can it? Her obsession with psychopaths and the workings of the brain make her suspicious." And again, in episode five, we pointed out her peculiar taste in music: "Quick shout out to the Lost fans, who'll recognize the Mama Cass Elliot song, 'Make Your Own Kind of Music,' as the song of choice Vogel puts on the record player before her abduction."

Bam! We've got ourselves a psychopathic serial killer who studies psychopathic serial killers.

Of course, this is only an educated guess; we still have four more episodes to find out if we're 100% right.

Foreshadowing appears to be a tool that the Dexter writers really want to milk in this episode. But as subtle as they thought they were being, they weren't subtle enough for us.

Case in point: when the episode opens at the crime scene in Cassie's apartment, Debra shows up to talk to Dexter. Quinn and Batista both make passing comments on how good it is to have her back where she belongs, working a homicide case. She does her little shoulder shrug and brushes them off. Mid-episode, after giving up on chasing Hannah, she tells Elway how she doesn't think she's cut out to be a private investigator, and he asks if she'll go back to being on Miami Metro's crappy payroll. Low and behold, at the hour's end, Deb is seen looking through her closet and pulling out a dusty old uniform. The preview for next week's episode confirmed what we already knew; we see Batista handing Deb a shiny police badge.

Next case: Dexter and Hannah's relationship. They're acting like school kids with a forbidden crush. Dexter finds any excuse to see Hannah, showing up at her marina because it was "on his way to work," and then inviting her to go chase Zach down at the Keys. They even have one of those adorable meet-the-parent type scenarios with Vogel in place of the mom. It's one majorly dysfunctional family dinner. But the best parallel comes when Dexter and Hannah are in a hotel room and she's all "you should go" but what she really means is "stay" - he does, and all we can say about that moment is dayum, look at dat ass! - and then at the end Dexter's all like "stay with me," and she does.

One last case: Zach's death. Dexter's intentions at the beginning were to kill off his protégé because he killed another innocent women: "What a waste, he could have had a great future." Then, when Dexter tracks him to the Keys, he stumbles upon a prepared kill room in his same fashion. There is even a set of knives in a black case on the bed. Though he doesn't admit it right away, Dexter is impressed at what a quick learner Zach is, since he never quite got that far in their lessons. Dexter decides to spare Zach when he realizes that "He was following the code without even knowing it" - he does have a lot of potential! However, Zach's fate was sealed since scene one, and it was complete by episode's end.

Vogel has spent much of the past couple episodes trying to convince Dexter not to kill Zach. Now, it seems it was because she wanted to do it herself. Vogel says at the dinner table, "I've always maintained that the greatest obstacle in life isn't danger, it's boredom." What better way to keep herself entertained than by playing a game with one of her psychopath experiments?

Dare we say Dexter was a bit heartbroken when disposing of Zach's body? He'll just have to make do with his blood son and without a spiritual son. And besides, cozying up with Hannah might help lighten his mood.

Tonight's episode set up Hannah, Dexter, and Zach to be like an adorable family of killers, with Vogel as the grandparent. But with Zach's murder, and Zach having the place of the son in this little scenario, we can't help but predict that perhaps this too is an omen. Could Harrison's life be in danger? That's just one prediction we're hoping we've gotten wrong.

Either show writers are running out material, or we're just getting really good at this. (We prefer to go with the latter.)

Follow Cultist on Facebook and Twitter @CultistMiami.

• Film and TV