Castle season 6 episode 15 is going to be one of the most controversial episodes this season as Castle and Beckett will be dealing with a real-life "Carrie" in the new case they are working on. Stephen King's first published novel may have hit the big screen for three times now with different movie adaptations, but this small-screen adaptation is something that you shouldn't miss. Unfortunately though, Castle season 6 episode 15 isn't airing tonight and ABC has not provided a clear explanation why.