He's one of those faces you recognize from countless movies. But for modern film fans, David Thewlis is best known for just one role - Professor Lupin in the Harry Potter series. He's played the part in " Harry Potter and the Order of the Phoenix" and in " Harry Potter and the Prisoner of Azkaban."

But he wants you to know that's not all he can do. Thewlis is also a published author and his new book, "The Late Hector Kipling" is a far cry from the ones penned by J.K. Rowling. It's what brought him to Toronto and the International Festival of Authors. And he comes by his ambition honestly. "I always wanted to write even before I was an actor," he shrugs.

But he admits his screen time has increased his success with the pen. "I've got already a good fan base, you know, and people have heard of me and yeah, I'm sure it's easier to do it from my position than a first-time novelist."

O.K. but what about the revelation that Albus Dumbledore is gay? Thewlis concedes that threw him for a loop, but not for the reasons you might think. "The funny thing when Alfonso Cuaron directed "The Prisoner of Azkaban, the first film that I appear in, he had the idea that Lupin was gay and he described my character like a 'gay junkie' .And of course Lupin turns out not to be gay because he marries Tonks and has children."

Thewlis is currently filming the next Harry Potter flick. But while that movie's debut is a while away, you can see him a lot sooner than that. He'll be talking about his new tome at the Festival at Harbourfront Centre Wednesday and Thursday nights.