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But in the show as a whole, up to that point, Shepherd Book didn't exactly scream "yet another spiritual guide" to me, particularly since he actually came across as more complex than some of the other characters.
See Buffy, season 2 with Jenny Calendar, Buffy season 6 with Tara, Angel season 5 with Fred, Serenity with Shepherd Book and Wash, even the Buffy season 8 comic book not saying who.
One of the strange men rushes wounded Jayne with a knife and Shepherd Book leaps out with some funky Kung Fu to incapacitate Jayne's attacker.
Then again, Shepherd Book could kind of work as one of the wiser-than-thou aliens ...
One of those questions, of course, was about just who the mysterious Shepherd Book was before he became a man of faith.