Answer:
There's one in every deck of cards and in a famous movie
If you have me, you want to tell me. If you tell me, you don't have me.
If it is absolute, it will corrupt absolutely.
Without this, H2O would just be 2O
The thinkers usually hold this body part
I touch the Earth, I touch the sky, but if I touch you, you’ll likely die. What am I?