One of the most famous stories Isaacs tells is how he ended up playing Lucius Malfoy. He originally auditioned for the role of Gilderoy Lockhart in Harry Potter and the Chamber of Secrets. The director, Chris Columbus, liked his reading but asked him to read for Lucius instead. Isaacs was incredibly frustrated because he was already playing Captain Hook in Peter Pan and did not want to be typecast as another children's movie villain. He read the Lucius lines with a bitter, angry sneer—intending to ruin the audition. Instead, his fueled spite was exactly what the producers wanted, and he was cast on the spot
