First things first: the bad news is your trusty guide through all things Dexter, Scott Tobias, couldn't be with you for last night's episode. In his stead, he has entrusted me to recap for you the Matsuka F-plots, the many colorful curses of Deb, and the spectacular denouement of Dexter vs. Miguel in last night's episode. The good news is, it was an amazing episode. In my opinion, it was one of the show's best, so good that you almost forgive them for creating Lila in season 2. Almost.
We began last night with Dexter believing that he had maybe finally reached his end. Trapped in the trunk of a car, with only the red glow of the tail-lights, his thoughts, and visions of Harry to keep him company, Dexter struggled to get free of his restraints as he struggled with his regrets about once again letting someone see the real, sociopathic Dexter. As it turns out, Harry was right. Monsters can't have nice things–like friendships built on mutual trust and honesty, if only because in order to knowingly be friends with a monster, you have to be a monster yourself. And as Dexter's brother, Lila, and now Miguel have demonstrated: Monsters aren't to be trusted. They'll end up killing innocent people, or kidnapping innocent kids, or recklessly murdering criminal criminal defense attorneys for personal gain then engaging you in a fatal cat-and-mouse game that seemingly ends in the trunk of a car. As Dexter put it last night while sweating in said trunk, "I. Am. Fucked."
Of course, Dexter was fucked, just not in the way he thought he would be. When the trunk popped open, all Dexter had to face was torture by stag night party boat, but for someone who struggles to make it through any social interaction, that's still pretty bad. Matsuka described the bachelor party wonders that awaited Dexter, "Premium bar, all you can eat buffet, and the finest adult entertainment." Dexter's response was a plastic smile and the thought, "Kill me now."
On the sailor stripper party boat (is there a sadder mode of transportation?), Miguel gave a seemingly heartfelt best man speech that included a few not-so-subtle in-jokes at Dexter's real persona ("Why don't you just stab a guy in the ventricle, ay?"), but also what seemed like a plea to get back Dexter's friendship. He talked a lot about the value of trust and wanting to bury the hatchet, but the only place that Dexter was interested in burying a hatchet at this point was in Miguel's chest. Dexter was beyond any kind of emotional appeal from Miguel, and was thoroughly obsessed with killing him, which I guess is the both the advantage and disadvantage of being a sociopath: you're never swayed by emotion of any kind.
From there on out, Dexter was thoroughly consumed with thoughts about killing Miguel. He walked around in a fog of anticipation, obsessed with the object of his murder lust, like a man in love (with killing killers). In meetings about the Skinner case, Dexter's thoughts wandered to planning the big event ("Maybe I could kill him in his car…it has that big back seat."). While processing cases, Dexter dreamed of his wedding night ("One glass of champagne, and Rita will be out like a light…the perfect alibi.").
But as Dexter began his pre-killing stalking ritual, he learned that Miguel's death would have to come a lot sooner than he anticipated. Laguerta's eyes were, for once, not clouded by emotion and she was beginning to suspect Miguel for Ellen Wolf's death–you could tell by the way she methodically circled the words "Black" and "Lincoln Navigator" on giant blow-up copies of Miguel's car registration. (Subtle, Dexter writers. Even when Laguerta's being smart on Dexter, she's never shown to be anything more than slow.) That night, while Dexter watched from his car–which, honestly, seemed to be parked dangerously close to the people he was supposedly surrepticiously watching–Laguerta sneaked out of her dinner date with Miguel to take a few samples from the back of his SUV. That would have been fine, except that since Laguerta can never not screw up an investigation, she left Miguel's door ajar–a fact that he quickly noticed, even though apparently he didn't notice his former best friend's car suspiciously loitering directly across the street.