Casting Harry Potter TV Show Reboot
11. Professor Quirrell - Eddie Marsan
Professor Quirrell is supposed to be a bit of a joke as a Defence Against the Dark Arts teacher, therefore casting someone like Henry Cavill was never going to work. Ian Hart brought him to life originally, sneering his way through the finale against Harry. Eddie Marsan is an actor who has appeared as both kindly figures and villains in his career, making him the perfect choice for the man.
Marsan is able to switch between intense and lovable on a dime. While Quirrell is constantly trembling and shaking, he should not be too incompetant - perhaps just able to blend into the background in any way. With his smaller stature combined with his ability to shrink himself into the shadows, Marsan would be an excellent choice.
The reveal of Quirrell as the villain was one of the best twists in the entire franchise and it is something that the original film didn't master with Hart. There seemed to be an assumption that everyone watching the film knew the ending, which in fairness they probably did. But, that mean Quirrell was often to be seen either talking to himself or avoiding contact with anyone. They effectively placed a 'villain' sticker on his chest. What is needed is a characterization that is both warm, if timid, and unassuming. While Marsan may look a bit demented in the image above, he is absolutely capable of pulling the rug out from under your feet - just like Professor Quirrell.