This is a great film. I watched it several times for my "French and Itialian Cinema" class, a course that frankly changed my college career. I wrote a paper about The Grand Illusion that I wish I could now find.
It's a Critic's Pick in the New York Times right now. Well worth watching their take. Watch all the way through to the end, I promise, you'll be glad you did. I laughed audibly.