There is so little of the mad genius about him that this line seems perfectly apropos.

If so, did they ever try to halt their mad genius ?

"Lately I've been getting lots of calls to play mad geniuses."

A mad genius, or a genial madman, however you like; it all comes to the same thing.

The man who painted her was a mad genius.

Dave is eventually revealed to be a latent mad genius.

Somebody was a mad genius, a wizard at thinking on his feet.

Waters had called it "a real act of mad genius".

He was actually something of a mad genius, but his deformities had made him into an outcast.

Somehow, I had become caught up in a desperate struggle between mad geniuses.