He is a 'madman' out on the ski slopes. [=he is an extremely daring or reckless skier]
He drives 'like a madman'. [=he drives very recklessly]
a celebrity being stalked by a 'madman'
(..) - Scott Fitzgerald talked about it. - Gil. Gil. Inez, you can fool me, but you cannot fool Hemingway. - I know. - Jesus Christ, I'm dealing with a madman here. OK. Yes! I did. I was with Paul for a few nights, because he's romantic, and he speaks French, and you were always working, and maybe it's (..)2011 Midnight in Paris