4. Casablanca

Everyone needs to believe in something bigger than themselves - even if it means making painful choices. No film illustrates this truth better than this one.
---
(I had the pleasure of seeing this movie in a crowded college lecture hall in the early 1970s, before films were readily available, so most of us had never seen it before. The audience reaction to the line following "Major Strasser has been shot" is the best moment I've ever had in a movie theater. Delirium.)