At the end of Castle Season 4, Ryan and Esposito experienced their first falling out, because Ryan ratted out Espo and Beckett to Captain Gates. The tension between the pair lasted way longer than we'd hoped, but their bromance eventually got back on track after Ryan took a punch for his best friend.

But could Ryan’s relationship with Esposito be tainted once again? Ryan knows about the relationship between Castle and Beckett, and chose not to spill the details to his partner-in-crime at the end of Monday's episode, "Murder, He Wrote." In the land of besties, that a big no-no.

So Castle fans, what do you think? Will Ryan and Esposito’s friendship remain intact once he finds out that Ryan knew about about Caskett? Or will Espo simply let it roll off of his back when Ryan explains the reason behind his decision?

Sound off in the comment sections below!

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