Remember that great A Serious Man trailer scored mostly to the sound of Larry Gopnik's head being slammed into a wall over and over again? This is kind of like that.
I love this teaser. It's not about any kind of narrative or plot. It just wants you to know that something seriously badass and violent is coming our way, and it will have a lot of scary Asian people, some of whom were in the first Raid film, none of whom you probably want to mess with, all of whom will probably get messed with.
There's not much else to say, though I should pass-on director Gareth Evans' request that you watch this with the sound turned up loud.