Accio, pics of Dumbledore! HBO’s “Harry Potter” series is underway … and we have a first look at John Lithgow in full costume.

The 79-year-old Emmy winner looks unrecognizable as the headmaster of Hogwarts, fully disappearing into the role. This show of commitment should calm down any fans who were worried about the professor being played by an American actor … John has the unenviable task of filling the legendary shoes of his predecessors, the late Richard Harris and Michael Gambon.

As soon as he was announced, John tried to get in front of the inevitable controversy that would surround his casting … saying, “I will be following the great Michael Gambon. I’m not an Englishman, although I’ve played one on TV. I remind everyone that I did play Winston Churchill on ‘The Crown’ and did just fine.”

Pics of John’s beach scenes come after HBO dropped shots of Dominic McLaughlin suiting up as Harry Potter for the first time.

The pint-sized spell-slinger looks every bit the part in round specs and a Hogwarts robe.