From the looks of it, The LEGO Movie tells the classic hero's journey story. An ordinary guy finds himself in extraordinary circumstances, and he rises to them.
There are just a couple twists on that: First, he's a LEGO man. Second, he is routinely assisted by Batman (and Wonder Woman, and Superman, and maybe Abraham Lincoln, though he seems to be on the fence). Check out the brand-new trailer for the movie after the jump.