Batista tracks down Arlene Schram, who's a trashy former drug addict, and Deb offers her immunity from any involvement she might have had if she'll come forward about Hannah, also threatening her if she doesn't, to which Schram asks for some time to consider. Even in the face of Deb's threats, Schram goes to Hannah and lets her know what's up, and we learn that the counselor who abused Hannah did the same to Arlene, so she's had good reason to protect Hannah's secret. Hannah promises she'll figure out what to do about Deb; she tries talking to Deb first, trying to make her see that Dexter is happy for the first time in a long time because of her, but Deb is like, "It's because I love him that I'm going to take your ass down." Following this, Deb gets in a car accident, and even though a blood test reveals higher-than-safe levels of antidepressants, Deb tells Dexter that she barely had taken any. He doesn't let on to Deb, but the seeds of doubt have been planted, and soon, he's asking Hannah if she's responsible. She convincingly denies it, acting terribly hurt in the process, but when Dexter gets the lab results from the water Deb was drinking in the car, it turns out it was loaded with an anti-anxiety drug. So either Deb set herself up, which seems like it would have been far too risky (and also possibly unnecessary, since she had every reason to believe that she'd be able to break Schram), or Hannah really did poison her. Obviously concluding the latter, in response, Dexter turns over Sal Price's pen – the one Hannah dipped in aconite and still has her prints on it – to Deb. Dexter then goes to see Hannah, and kisses her under the mistletoe before saying he's sorry – just as Deb and the rest of MM comes to take her away. Her last words to him are a whispered "You should have killed me." Merry Christmas!
We open with, in three-quarter speed, Dexter raising a knife over a plastic-wrapped victim in the familiar way... only he's aged up to look around sixty at least, which only makes me want to jump off and watch the Six Feet Under series-ending montage for the jillionth time. I will soldier on though, as DVO tells us he's never thought about the future or growing old, logically enough given that "the future has never been kind to people like me." He stabs his victim and maybe it's the slowed speed, but he seriously looks like he's about to take a nap on his feet, which given his advanced age is kind of hilarious. We then see him loping up to Hannah in her greenhouse (woman has kept herself up, I feel I must point out) and when she sees him, she smiles warmly and comes over for a hug. Someone then emerges from the house holding a basketball and wearing workout gear, and although the character is listed as "17-year-old Harrison," the actor, Lucas Adams, is older, so I don't think I'm breaking any laws by reporting that he's grown up nicely. He and Dexter exchange goodbyes (no words for Harrison to Hannah), and then, as Dexter kisses Hannah and DVO talks about how a real future seems possible now, the camera swirls around them, transporting them and us back into the present, their lips still locked. DVO adds that growing old is looking not only possible, but appealing; any further thoughts on the subject are interrupted by Dexter getting a call from the Department of Corrections reporting that Hector Estrada -- the ringleader of the gang that killed his mother, as Captain Jack told us last episode -- is up for parole and the hearing is that very morning. After she apologizes for the short notice, Dexter gets off the phone and tells Hannah what's up, and a little exposition follows in which Dexter tells her that the other members of the gang are dead (by his hand, it's heavily implied), and Hannah, rather cheerfully and even a bit proudly, speculates that Estrada will be joining them soon. "Look at it this way: Maybe it's the universe giving you a Christmas present." Dexter smiles and notes that only she would see it that way and I'd rip on that were it not for the fact that it sounds about right.
Estrada -- who's doing a bit of an old-man walk as he's led to his spot for the hearing -- is wearing the typical prison-orange jumpsuit as Dexter, sitting in the back, looks at him askance. DVO wonders if killing Estrada could close a chapter in his life and open him up to a future with Hannah, and then the lead panelist announces that they find Estrada meets the requirement for release under the "Compassionate Release Statute," and common sense suggests that means he's dying. The panelist asks Estrada if he understands the terms of his release, and in a somewhat quavery voice, he says he does and that he won't screw up. The panelist then invites any victims present to enter a statement either for or against the board's decision and of course Dexter does not speak up, because while he wouldn't want Estrada to know his identity, he also is interested in, let's say, seeing to it that Estrada won't suffer long from his "terminal illness." No one else speaks, which could be for a lot of reasons, but is also a reminder that people besides Dexter are actually required to be in the office once in a while.