A new Borderlands 2 video introduces the backstory to the game's Tiny Tina's Assault on Dragon Keep DLC.
Tiny Tina and Brick have been captured by the Hyperion and fear they won't be able to make it home for their friend's funeral. Tina suggests to Brick that they aren't being interrogated by Hyperion forces at all but have rather been kidnapped by an evil wizard. In fact, he's not even Brick at all but a godlike Siren, and thus should be able to easily break the chains in which he's bound.
Brick lets his imagination take hold and battles the evil wizard and his allies by punching them over and over.
This naturally leads directly into the DLC's intro, in which Brick demands to play as the Siren, Brick, who is the prettiest of them all.
Tiny Tina's Assault on Dragon Keep was released in June.