Michael C. Hall is likely on the verge of his fourth Emmy nomination for Dexter when the Academy of Television Arts & Sciences announces the 2011 noms on July 14. He’s earned every one — and deserves a win one of these days — as a truly and consistently captivating presence on an uneven series. The first promo for season six leaned heavily on footage from previous seasons. The new teaser trailer offers just Hall in closeup, that intense gaze, and a droll voiceover (“I’m feeling like my old self again”). And that’s all we need.