LILYA 4-EVER (2002)
Generally, a "message movie" is a very somber affair.  These movies sit you down and have a talk with you like a stern authoritarian.  That's not to suggest that Lukas Moodysson's Lilya 4-ever is some kind of great romp.  This message movie's issue is one of the most important in the world today, child sex slavery, and as such, it's one of the most shattering and depressing films I've ever seen.  But it's told with such gleeful punk rock verve that it manages to make you feel deeply about its characters without feeling bad about yourself.  Every element of Lilya 4-ever is a propellant, from the heavy music to the rich cinematography and everything in between, most remarkably, Oksana Akinshina's shockingly honest and heartbreaking performance as Lilya.  If your message needed a face, you couldn't ask for a better one.