Saw this growing in a St. Louis shade garden-zone 6. It's the plant in the middle of the photo. The leaves look like a baseball glove or fingers.
I saw this plant on a garden walk two hours away from my home so I can't check if it has the red sap.
The first thing I thought of was bloodroot, too. I have it growing in my woods. Like raeben, I've never seen one with leaves like that before. It's said that there can be significant variation in the appearance of the foilage --> http://www.illinoiswildflowers.info/woodland/plants/bloodroot.htm which leads me to think that it is indeed bloodroot (Sanguinaria canadensis).