Eli Roth put on 35 pounds of muscle to play Donnie Donowitz, “The Bear Jew” and learned to cut hair for the role from producer Pilar Savone’s father Umberto at his salon in Beverly Hills. When asked how he got into the violent, baseball bat-wielding mindset of “The Bear Jew”, He partially attributed his performance to the historically accurate costumes: “Being in wool underwear will make you want to kill anything.” He also stated (in a separate interview) that his girlfriend had secretly added some Hannah Montana music onto his iPod; when he listened to it, it inexplicably made him able to tap into the violent nature of The Bear Jew.