La ragazza con la valigia

This may not be a very intuitive observation, and it's even partially stolen from Pauline Kael (at least the Walken part is), but I think Claudia Cardinale has the same thing Christopher Walken has, where you're never sure if there isn't some part of the character you didn't see coming lurking somewhere, ready to jump out and surprise you, just the feminine version of it.

I assume it's (in both cases) not really a method thing, but that they're both actors who are able to bust out all kinds of moves, moods and vibes with ease, confidence and competence alike. Not necessarily coming from training, but raw talent.