Paging febobe and other Lewis scholars...

Do you happen to know where Lewis says something about being able to "smuggle all manner of theology under cover of romance"? It's not the "past watchful dragons" quote, which I've found; I heard it in a paper at PWD, and I'd like to use it in my Theology paper, but I don't know where it's from.
Thanks!

WHOA!

I just saw a Narnia commercial during Mythbusters! It looks SO COOL!!
*counts the days*