Castle has always been a procedural, even if a character driven one, and this episode is of course no different. Therefore, it doesn't take long for Castle to pack up for an impromptu weekend with his lady in D.C. and just "happen" to stumble upon a piece of evidence in her classified case. Like the overgrown child that he is, he decides he just has to investigate even when told not to. It's out of sheer curiosity and the hope that if he helps Beckett solve it fast, they'll get more time together (you know, not realizing, even after all of this time, there will always be another case and the ones she is working now are matters of national security) so he calls up old pals Esposito (Jon Huertas) and Ryan (Seamus Dever) for some very minimal aid. It's a way to get the gang back together, but again, in a very minimal way. It gives Esposito and Ryan some brief face time but not anything real to do. They're basically sounding boards, and that means extensions of scenery. It's a shame and will be a huge waste of their talent if it is a long-term plan solution to keeping the original cast active.
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