We have the third trailer for Harry Potter and the Half-Blood Prince below. This particular installment of the Harry Potter franchise, I understand, needed to excise a lot of the book (it makes little sense to me that they are making Book 7 into two movies, when it’s book 6 that really warrants the two books). Half-Blood Prince is actually my favorite of the series; it’s sort of the Empire Strikes Back of the franchise. In it, Draco goes fully evil, Snape may or may not finally go to the dark side, and Ron deals with his hormones.
David Yates (the BBC’s “State of Play”) directs, as he did the previous installment, and as he will the final two. Here’s the trailer: