Mad Men isn't the only AMC drama with cool opening credits by hip artists. Turn, a new show about Revolutionary War spies, features an opening theme song by the National's Matt Berninger and the Civil Wars' Joy Williams. With Berninger involved and the often-bloody subject matter involved, "Hush" is appropriately dark. He gravely intones, "The snake's in the garden / Blood on the ground / I can't wait anymore / I can't wait anymore," as Williams repeatedly whispers "hush" over sepia-like animation showing Patriots decoding clues, covertly passing notes, and getting hanged. The series stars Jamie Bell and premieres Sunday, April 6 at 9 p.m. ET.