
[in a 1984 magazine interview] The characters I`ve played until now have been very sick people. These people are emotionally or physically damaged. Since I played killers so well, they wanted me to play a killer the next time. I used to call my roles "dog-eating" parts; you know, the director says, "We need somebody to bite a dog in this scene. Let`s call Ironside".
(imdb.com)