There was a fic a million years ago that had Sam and Dean travelling the country, but they were actually the serial killers Henriksen thought they were. I think they eventually got caught and put in a maximum security prison, which they broke out of. Now, I'm not actually looking for THAT fic, because I'm pretty sure the author deleted it and left LJ long ago, along with telling people she didn't want it shared (shame, 'cause I want to reread it. Sigh.). Edit: I didn't think it was possible for anyone to find it, but I'm pretty sure the one I was thinking of here is
Darker Shade of Black. by sardonicsmiley.
But I'm looking for similar fics now.
I just read
Blood in Your Mouth by saltandbyrne on AO3 and that's what made me crave more. There's just something so sexy about the boys actually being evil, but not supernatural evil, just human evil. (Yes, there is something wrong with me, I will be over there -->) There are bonus points for the more fucked up the boys are (like the fic I referenced, with implied necrophilia).
(Uh... I thought there was a serial killers tag, but I can't find it. Crap. I hope I tagged this right!)
p.s. this is actually
annabeth posting from a new, going-to-be-mostly-public journal, and I'm mentioning it because I know sometimes I get searched and my regular journal is locked.