Dexter Morgan (Michael C. Hall) goes off-the-rails, along with the show itself. I'm really trying to see the logic of "Nebraska", which almost exists in its own little bubble. I understand it wanted to show what happens when Dexter loses the calming influence of his father's code, and instead latches onto his darkest impulses—symbolized by his illusory dead brother Brian (Christian Camargo), as a psycho Jiminy Cricket—but this was still a bizarre mid-season indulgence. My guess is the writers just thought it would be fun to have season 1's The Ice Truck Killer return, while simultaneously dotting some i's and crossing some t's from season 4's Trinity Killer arc, but the result was a very discordant hour.
There were moments of "Nebraska" I enjoyed, but ultimately it was a head-scratcher. Dex wasn't fully unhinged throughout (as I'd have liked), so the influence of Brian just dissolved into nagging and silly arguments. Returning to the dangling plot-threads of season 4 felt like a backwards step, and the clarity over why the Mitchells never told the police that Dexter was their mysterious family friend "Kyle Butler" wasn't that surprising (they simply decided to keep Dex's cover, believing he was trying to help them). Still, the storyline with Jonah trying to coerce Dex into killing him once his cover was blown, as he didn't want to live with the guilt of what he's done, wasn't too shabby—especially as it ended with Dex channeling Brother Sam in refusing to kill Jonah and instead suggesting he forgive himself. However, less satisfying is how, when you stop to consider things, this whole road trip didn't accomplish much.
Overall, I just find it very odd that the writers apparently have so little faith in season 6's storylines that they've effectively spent 95% of an episode's runtime typing up a loose end from two seasons ago and bringing back a very old guest-star. It was just too stupid and unintentionally hilarious to work (Dexter stopped his car to pick up pretend-Harry on the outskirts of Miami?), and I'm just going to try and forget it ever happened.
- Holly, the "whore" who escaped Travis and Gellar's clutches, certainly seems to think there were two people... but that's probably a weak attempt to make us rethink the blatantly obvious. She never heard two separate voices, or saw two separate people, so she was mistaken. Travis is just dealing with his own version of what Dexter was going through with "Brian" on this episode.