If you were wondering what crazy capers Jack Black was going to get up to on the red carpet for the premiere of "Year One", the caveman/buddy movie thing, well wonder no more...

Here, my beautiful moles we get the full range of Jack's spectrum. Let's go through them one by one:

SERIOUS FACE. here, Jack is showing us with his finger that the number ONE is important. This is because the film is called YEar One. This fact is indisputable, hence the serious nature of Jack's face.
THE IRONIC CHUCKLE. Here Jack is showing that he is in on the joke. He's one of the guys. He knows you're all laughing at his funny tummy, but that's OK - he finds it equally as funny! hahahaha!
ROBOTIC! In this snap Jack is displaying a cultural reference point from the early 80s by doing a static robotic manoeuvre popular with 'breakdancers'. He is doing this both because he is having his picture taken next to an awkward teenager (this puts the boy at ease - he's being given a masterclass by his comedy sensei) and also because the public find it extraordinarily funny.
STRONGMAN. This is a common one for Jack, having spent most of Nachos Libre phoning in this face. Women find this face endearing and funny because, y'know - he's a fat guy pretending to be tough and handsome! hahaha!
Oh piss off Jack.