inception

--spoiler--
cobb: what do you want?
saito: inception. is it possible?
arthur: of course not.
saito: if you can steal an idea, why can't you plant one there instead?
arthur: okay, this is me, planting an idea in your mind. i say: don't think about elephants. what are you thinking about?
saito: elephants?
arthur: right, but it's not your idea. the dreamer can always remember the genesis of the idea. true inspiration is impossible to fake.
cobb: no, it's not.
--spoiler--