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Castle Season 4 Episode 21 News

'Castle' reunites 'Firefly' costars Nathan Fillion and Adam Baldwin in 'Headhunters'
Castle's Firefly Reunion: Can Adam Baldwin Lead Castle Back to Beckett?
Castle “Headhunters” Season 4 Episode 21
Spoiler Photos of Castle Season 4, Episode 21: "Headhunters"
Castle Promo for Season 4, Episode 21, "Headhunters": Rick Gets a New Partner!