Wicked

If you haven't seen the musical, please do. Absolutely brilliant. I won't ruin the experience by giving away the premise or the plot. Suffice it to say that while being a thoroughly entertaining comedy/drama it is full of profound life lessons about identity, friendship, goodness, and truth. It just might tie with Les Mis for the honor of being my favorite show ever, not in soundtrack content (it would be hard to outdo Les Mis for quality of score and lyrics) but in overall caliber of story and characters.