In the pilot, it's made clear that Martha is already living with Castle.

I thought this was the movie version of a book version of a re-adaption of the movie version of the book Battle Royale, designed for an American audience?

I was thinking one reality for Alexis & Martha, one for Castle's dad, and for the 3rd…aw shucky ducky, why not have good ol' Cpt. Montgomery alive in that one.

Nanashi, hopefully Lanie will take care of that next episode.

I liked the episode too overall.  The interview with West Side was fun, Tim Guinee was suitably creepy, & I loved the awkwardness with which Gates expressed appreciation of her staff—it's like it pains her to say nice things.

This tends to happen whenever the show goes into serious-emotional mode.
Sometimes the difference is so stark, I feel as if I were watching Awake.
The effect would be hightened if they killed off Alexis in one reality, and Castle started making appointments with Beckett's shrink.

If the promo for Ep.#20 is accurate, it looks like Castle is going to spend most of next Monday night picking up girls & trolling Beckett.  Should be fun.

Eh, I think Castle only grew one.  To earn the full pair he should have confronted Beckett directly about what she said.  It doesn't take much gall to go the passive-aggressive route.

While the NYPD was conveniently rounding up suspects, the FBI was busy filing the necessary paperwork in conjunction with DHS to be able to begin the waterboarding.

I agree with Ack Ack.  At PaleyFest it was made pretty clear that C&B are going to hook up before the end of the season, so expect the show to get a little soapy this month.
In the past, AWM and Co. would begin every relationship discussion with "herp derp Moonlighting curse…" but in recent interviews he tends to…

I wouldn't say that the show needs more Alexis…although she has vastly improved as a character since they got rid of her boyfriend.  
They used her well in this episode and in the 2-parter: she appears just often enough to remain relevant, and either makes Castle look good or provides some comic-relief.
…now if only…

Gates would probably be most effective if she patrolled the precinct, smacking her detectives & Castle on the head whenever they uttered a cheeky one-liner.

Thankfully "Faux-dette" never became as obnoxious as "exstalktion" did in "Till Death Do Us Part"

Ryan got married at the end of 4-11 "Till Death Do Us Part" back in January