No, it wasn't a dream, Castle. Watch Rick and Kate interact the morning after their big night in this amazing clip from the Season 5 premiere.
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ABC has released the first promo for Castle Season 5. It gives us an intimate look at the morning after.
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Castle Season 5 Episode 1 Quotes

The fact is that I admire your loyalty and hope you can feel that way for me someday.

Gates

That's going to leave a nasty scar. Every time you see it, think of me.

Beckett

Castle Season 5 Episode 1 Music

  Song Artist
Song All I Could Think About Was You Robert Duncan
Song I Just Want You (remixed) Robert Duncan
Song Countdown Robert Duncan