I want to find a song with the theme of " seeing through his/her act".?

I know I heard one once before, but I can't remember ANYTHING about it. I'm not looking for any one song in particular, just one with the basic theme (basis of the song) as seeing through an act or lies. Thank you!!!!!! I don't care if it's poppy and uplifting or sad and depressing or stuff. If you know of a song but don't know the name, post some lyrics (words to the song.)