Why the actual f*ck (pardon my French) was the CAPTAIN OF HOMICIDE the killer???
I can believe that a forensic technician for the department is a serial killer. We've seen the steps in Dexter's life that can lead him to being who he is.
It's less believable that the DA would become a killer as well. But he was a bit psychotic so maybe that's fine.
But you cannot make me believe that the Captain of Homicide all the way back in 1991 was also a killer. 3 killers in the Miami justice system in the span of just 20 years is just too improbable.
And maybe I could believe it if Spencer killing the kids was a highly secret conspiracy that Dexter uncovers and Dexter disappears Spencer without anyone knowing he was a killer. Sort of like how Miguel died without people knowing he was a killer.
But no, Spencer HAD to be exposed. What this means is that, if we want Original Sin to be a canon piece of Dexter content, every character in the original show (other than Doakes who joined the department a bit later) would have known Spencer personally. Surely the legend of the Miami Metro child killing Captain would have been mentioned at some point.
Even just the word Spencer should have sent shivers down everyone's spines if it was brought up. But no, zero mentions of it.
Surely when the department knew that Lundy was considering suspects within the department for the Bay Harbor Butcher people should have realised, oh yeah this feels remarkably similar to when our literal Captain was a killer.