Great little clip from Jaws. I love Richard Dreyfuss' reaction to Quint singing. He's obviously annoyed with him, but he's not putting on a generic "annoyed" expression. Instead its hidden in a fake smile. There's some great eye darts and mouth changes that let you know he's not happy with the situation. It may be obvious, when animating, that your character should be happy, or sad, or angry...but are they trying to hide this emotion behind another?