Wow, that was a quite a roller coaster! Very exciting episode, although, now I can't really imagine, what happens next.
Dexter takes Hanna to a small boat trip, but she looks stiff and pale and hardly enjoys it: she's afraid of water since her father nearly drowned her, when teaching her to swim. When she asks Dexter if he ever was scared like that, he pulls the usual self mumbling "I don't know", but very conveniently he is called for work: to take a look at a burned man's body. "It was a suicide", concludes one weird arson investigator. But it takes just one more burned person to make Dex suspect that the arson guy is responsible for this.
Isaak has a problem: Koshkas sent two guys to kill him, sadly they are nothing like those amateurs from Colombian drug cartel he could finish with one hand, they are professional hitmen, so to survive he needs help. And who could help him if not Dexter Morgan? When Sirko outlines the situation and offers to stop his vendetta, if Dex would give him a hand, he gets in response: "I'll take my chances". So arrogant. But secretly Dexter doesn't want Isaak be killed by somebody else, either because he wants to end him himself, or he just feels they have a lot in common.
So Isaak has no choice but to take Hannah hostage. He threatens Dexter that if he doesn't get help, his associate, Jurg, will kill her. Dexter runs to his sister and asks her to pull off the surveillance. She's obviously unhappy when she learns who he's doing it for, but eventually agrees.
Dexter stabs one of the killers, Oleg, easily, at the firing range, in the broad light with people around. To get to the second hitman, Benjamin, Dex wants to let the guy follow him to a safe place and finish him there. Also, while having a video call with Hannah, Dexter takes a screenshot of her, which helps him realize that Jurg's keeping Hannah in the house of one of the Colombians Isaak recently killed. He asks Debra to find out which house this is.
Benjamin follows Dex to a cargo ship, as expected, and is successfully killed there by Isaak. However, before that, the guy mentioned the place where he was going to to George, who was afraid Sirko would brutally murder him if he stayed alive, so George appeared there as well and shot Isaak. Dexter wanted to call an ambulance, but dying Sirko asked him to bury him at sea instead, to be reunited with Viktor.
Hannah tries to escape and is attacked Jurg. She kills him with a lamp, but he wounds her, so she passes out. Debra finds them and calls an ambulance. In the hospital Hannah asked her why she just did not let her die, and Deb replied that she's not like them and she doesn't want to feel responsible for anyone's death.
When Dexter enters the ward, she leaves, after confirming that Sirko's been taken care of. Dexter then answers that question Hannah earlier asked about him ever being really scared. He said he was twice: first, when his mother was chopped in pieces in front of him, and now, when he thought he might never see Hannah again.
Maria comes to Tom Matthews and tells him about her investigation on Bay Harbor Butcher case. At first he sends her to hell, but then he agrees to help her if she helps him ensure his pension first. I think he wants to double-cross her.
And Quinn beats up George for sleeping with Nadia (George did that to pay back to Quinn for not returning his calls) and leaves the club with her.
So, finally, Dexter has accepted his feelings for Hannah, though, looking back at his history with women, I have a feeling she won't survive (in the best case scenario, won't stay out of jail) and by the end of the season it'll be over.
Maria's investigation is finally moving somewhere, which is certainly promising, but I still can't figure out, how is it that she suddenly became good at this job? Where were her wonderful insights before?
I was also sad to see Isaak go, I liked this character a lot. Oh well.