Durand is a famous neurologist, so he knows exactly what's wrong when he begins to have hallucinations and nervous twitches. He's experiencing a neurological disease he doesn't understand how to cure from within his own body. His daughter requests to help him, hoping she can cheer him with fun activities. She takes him to see Grimaldi, a popular clown capable of putting a smile on everyone's face. Her cure works - at least momentarily. Durand laughs along until he recovers from his malaise and goes to work the next day, refreshed. Meanwhile, Le Febre awakes to a neurological horror - everything hurts, all food and drink makes him nauseous, and he can't manage to even put on clothes without help. He heads to the doctor's consultation he's been avoiding for months - the famous neurologist Durand. As Le Febre describes his condition with much difficulty, he watches Durand's face descend into grayness and twitching, realizing the horrible truth. The expert who was supposed to save him is similarly afflicted. He begs Durand for a cure, and the neurologist tells Le Febre he ought to go see Grimaldi the clown, whose cheer will reduce his symptoms. Horrified, Le Febre tells Durand that he is Grimaldi.