After three very wonderful episodes since the start of the new year, as other reviewers have noted, this seemed like a "filler episode" (ya can't throw romance and flirting between Beckett & Castle EVERY episode though the fan base would beg to differ). Now more new episodes until March as you all know.
For the most part, the comedy fell very flat and as noted, no romantic tension whatsoever. We did get a new facet on Castle's personal life, we've never really thought about his father before (though even the very first episode in Season 1 joked about Martha's many men when she and Alexis sprung Castle from jail) and this episode brings that question to the forefront. Makes sense to me, Beckett lost a parent, Castle is helping her find closure. Castle has never met one of his parents, I wonder if Beckett through her detective resources helps Castle find his father? Beckett was reluctant to talk to Castle about her mom for a while, Castle likely will be reluctant to talk to Beckett about his unknown father for a while... good counterbalance if you ask me, enriches these two to hopefully come together in a deep relationship two or three seasons from now if popularity stays or grows.
Okay, I digress... as for the actual murderer, my record for guessing right is pretty poor, but I got this one right... kinda stuck out like a sore thumb if you ask me... simply because other suspects were way too obvious as not being the actual murderer thanks to how the story was told.
On the positive side, Molly Quinn can really hold her own. She continues to really play Alexis in such an endearing way... you can't help but love Alexis.
One last note, perhaps I'm way too critical, but the two Jose Molina written episodes (other one is 'Famous Last Words') are the two lower scoring episodes on TV.com, though still good. You've got one more strike Jose... pun intended.