1. The time Castle dressed as a "space cowboy":
2. The "I was aiming for his head" gag:
3. And the "you better run" gag:
4. Name-dropping the Serenity:
(As we all know, the ship from Firefly is called Serenity.)
5. Also a 'shiny' drop:
6. Wonder where Castle learned Mandarin?
Oh, right.
(For those who don't speak Mandarin, that translates to:)
7. There was the time Castle didn't get the appeal of an old sci-fi show:
Which sounds pretty familiar...
8. Adam Baldwin's appearance on Castle can't have been a coincidence:
9. Especially after this very conspicuous scene involving a brown coat:
10. And finally, there were these blue-handed signals from Castle:
