Quickly, Natalie whipped up a ham sandwich, but Charlie refused to eat it; instead he feverishly tried to rewrite what Monk had erased.

"You need to eat something" Don insisted.

"Your brother's right" Natalie assented, concerned about the fact that the mathematician hadn't eaten for over a day. She stood next to Charlie, carrying the sandwich in a plate.

"He just had to erase the most vital equations." Charlie seethed to himself, as he reentered his own little world.

"He sure did" Don assented, surprised at how through Monk had been. It looked as if Charlie hadn't written anything at all in the parts that he hadn't retouched. The sleuth's eccentricities, which Don had seen in L.A and here in New York, made Charlie look socially and emotionally well adjusted by comparison.

"Charlie took pictures of the pigeon's head" Natalie said as she took out the paper copies she printed for Monk from her purse.

"The bird was beheaded with a Wüsthof Trident knife" Monk said as the agent looked at what Natalie had given him.

"What makes you say that?" the agent asked. He was used to medical examiners figuring this out, not ex-cops with severe OCD.

The sleuth gave a very detailed explanation, which satisfied Don, who finally realized that Monk knew what he was doing. The sleuth's observations were very astute, and the result of a trained, as well as brilliant, eye. Don could not believe that he didn't see some of the things that Monk had pointed out.

"And it was alive when it was beheaded" the sleuth added.

"But why a pigeon?" Don mused aloud.

"I've been asking myself the same question" Monk commented.

"You and Charlie think that Hans' work at IBG had something to do with his murder?" Don asked.

"Yes." Monk told him.

"I checked him and the company out. I couldn't find anything suspicious" Don said with a sigh and a shrug. However, he still worried that the pigeon head was the murderer's way of threatening his younger brother's life.

"Charlie, you really should eat" Natalie nagged the mathematician, as Don and Monk talked.

Again, the mathematician ignored her.

Monk tried to straighten one of the papers, filled with equations, that Charlie had lying around. The sleuth could not bear to see it like that.

"Step away from that paper!" Don, with a fierce look, ordered Monk as if he were a suspect under arrest. The agent worried that Adrian would again erase equations.

"Charlie refuses to eat" Natalie said worriedly.

Don firmly took the pencil from his younger brother's hand and coaxed him into eating the sandwich.

"Have you made any progress?" Monk asked with a grimace as he saw Charlie ravenously eat the sandwich in a few bites.

"I think I know what Hans was working on" Charlie began but before he could continue, Monk yelled "Oh my God!"

TBC