Hey, speak of the devil in a silver suit! He looks around shiftily as he enters his home, and then heads down to the basement, where he drops off a rather large new bucket of kerosene. He then opens up a closet to get the silver suit -- only to have the suit attack him, as Dexter is in it. Inconvenient and clumsy, but points for style; plus they had to find a way for the guy not to see his face...

...and speaking of which, Dexter is burning large amounts of cardboard or incense or something to give his plastic kill room an appropriately smoky atmosphere. After some typically detached yet snarky comments, Dexter asks who Bobby is and the PA tells him he was his best friend when he was twelve and it was his idea to start the first fire the PA set, "but then he died and I got caught." He got sent to the "nut house" for something Bobby did, and now he only hurts people because of Bobby. Dexter's like, you can't blame your kills on something that happened to you when you were a kid -- OH WAIT -- and here we are, back to Dexter being influenced by the most random people crossing his path, and he decides to decide that the Dark Passenger construct JUST LIKE THAT and not kill the PA. I mean, probably no one except Joe Reid likes the DP bullshit less than I do, but this is a ridiculously unearned way to get rid of it...

...but when Deb and the rest of the MM idiots arrive at the scene, apparently clued in by an "anonymous" tip, they find the guy unconscious on his basement floor, with no evidence of the kill room but with the silver suit on prominent display. Still, though, is that enough evidence to link him to the murders? Batista said there were tons of sites that sold them; is there anything non-circumstantial here? I mean, this whole set of events just doesn't work. So Dexter has decided to take personal responsibility for his actions. So what? Why does that translate into not getting rid of a kid-killer, especially when the evidence available to convict him is shaky? He started killing again a month after spending years in a psych ward; what happens if he gets out of prison? I accept that the show has to use these villains to advance Dexter's character, but not that the advancement has to make no sense.