Well, he is clearly not - as readers of Harry Potter and the Half-Blood Prince might suppose - Professor Albus Dumbledore!
But no! This time Harry's mentor is that other white-haired movie-wizard, last seen (allegedly) heading for the Grey Havens --- Gandalf...
If you doubt me, just bring them face to face and you'll see I'm right!
DON'T FORGET: Tomorrow is the closing date for entries to the current Caption Competition!