The opening dates have been changed a few times (it's now July 15), and the series of books is complete. We know who dies and who lives. We even know who marries whom and what they become when they grow up.
But the makers of the sixth film in the franchise, "Harry Potter and the Half-Blood Prince," are convinced the boy wizard remains a draw.
The final trailer made its online debut Thursday at harrypotter.com and debuts in theaters May 1 with showings of "Ghosts of Girlfriends Past."