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'
(..) This is a seller's market. Coke is fucking dead as... dead. Heroin is coming back in a big fucking way. All right, give me three grams of madman. If it's as good as you say it is... I'll come back and buy another thousand. Well, I just hope that I still (..)1994 Pulp Fiction
(..) Now, there's nothing wrong with these two. This is real, real, real good shit. But this one is a fucking madman. Remember, I just got back from Amsterdam. Am I a nigger? Are we in Inglewood? No. You're in my home. (..)1994 Pulp Fiction