Blueberry pies are tough, because there's so much liquid, they tend to turn to mush pretty quickly. But this one's pretty much foolproof. You pre-bake the shell, then cook down 1 c. of blueberries over the stove, with sugar, water and corn starch. Basically, you get some blueberry sauce out of that. Then fold in 3 c. of cold, fresh blueberries. The sauce creates a gel, and the whole blueberries stay intact. Then, just spoon it into the shell, and you're done.