"We may not have noticed it at the time, but this conflict has been set up from the beginning. Even “Undead Again” hinted at it with Beckett and Esposito on one side and Castle and Ryan on the other. It’s been the theme of many an episode but only now did it have very big, very real implications. The most heartbreaking part however, was that Ryan didn’t have Castle to fall back on in this case. He was left on an island and he made the tough choice on his own. It was the right choice and it showed a level of growth in the character – he was his own man, making the grown up decision. He paid for that decision though. And the last we saw of him, he was alone. Seamus Dever deserves so much recognition for his work in this episode."