Castle's research about the murder of Beckett's mother has damaged his and Beckett's relationship. For Beckett, the new case is going to be their last, for Castle it's his last chance to reconnect with Beckett.
The season opener's case is more of a piece of cake, but Castle's attempts to reconcile fail. For once, it doesn't work to be his charming self, and in the end he accepts defeat. But it's his daughter Alexis who finally gets him back on track: Alexis's boyfriend troubles open his eyes and he realizes that justifying his past actions won't work, and he returns to Beckett to simply say he's sorry.
A photo shoot at the police station, a Russian mobster, poker... No doubt, Castle is back. Their new case is not one of the biggest mysteries, though it's a nice surprise when the body is stolen by armed and hooded criminals. As it turns out, the victim worked as a drug mule and died before he delivered the drugs, so the drug dealers have to take the body as soon as the victim is no longer hanging in the tree (Understandable, right?). Unfortunately, he was murdered by the Russian mobster he owed. He would have been able to pay when he had delivered the drugs. Well, that's life I guess. Or bad luck. However, Beckett and Castle catch the culprits.
And they do it their way. The tension between the main characters is well delivered, there is just enough to flesh out the problem that Castle's curiosity caused, but it's still enjoyable to watch. And lucky for them and for us, Castle figures out how to repair their relationship.
This was a highly enjoyable episode.