Hooray, we get to see Alexis's forehead and eyebrows again! I've never missed a forehead so much. We got the bangs back later, but at least they were somewhat backswept and parted instead of straight down and shadowing her eyes. It's movement in the right direction.
And Castle's right -- someone needs to tell Ashley that "flaxen" means pale yellow. It's totally the wrong word for a redhead.
I guess the promo last week must've been very misleading, because it gave me the impression that Alexis and Martha would be held captive by a killer. Glad they didn't go that route, beyond having Castle worry about the possibility. Also it was a nice departure from the usual format where they bounce from one innocent suspect to the next to the next. They spent most of the episode focused on one guy, and he actually was involved, though there was still a twist at the end as to how. And instead of the revolving door of suspects, it was more of a classic mystery structure where it turns out to be one of the three featured guest suspects -- with all three of them being legitimately involved rather than red herrings. Indeed, they played with our expectations by making the sweaty guy look like the usual easily-discarded Suspect #1, then revealing he actually had been involved all along.
And in another format departure, the killer gets away. No doubt he'll be back later in the season. I guess we've already had the arc about Beckett's white whale, so now it's time to give Castle "one that got away," one he blames himself for, to make it more personal. I wonder if this will just be a couple of episodes or if they'll make more of an arc out of it. (Come to think of it, are they ever going to revisit the mystery of who hired the killer of Beckett's mother?)