In my ocnvoluted memory I recall a movie about three kids (older 12ish girl, younger boy(s?)) being chased by bad guys and carrying a notebook of their recently killed father.
Book gets destroyed, but one of the kids has memorized it.
Turns out it is the transcript (wirtten in Spanish speed writing) of a Hitler meeting filmed (but without sound) which cannot be interpreted by lip readers.
I’ve tried to come up with some means of searching for this, but I got nuttin’
Does this ring a bell for anybody?