Wilson wasn't still around, and Cuddy made a mental note to present her apologies tomorrow. Meanwhile tonight, she went back to her apartment to think.

As she had told the Maestro, her questions had only multiplied. Who on earth was he?

Okay, Lisa, she told herself, work out what you do know. Make it a differential.

Fact #1: Whoever he was, he was a doctor. He had the most brilliant medical mind she had ever encountered in her entire education. She saw no possible other choice for his past vocation.

Fact #2: He was hiding over there. That was obvious enough, but from what? His leg? Society in general? He was definitely touchy about his leg, but why would that make him give up the chance to practice medicine? It almost seemed that it would work better the other way, the job providing a distraction and something for him to dig his teeth into.

Society in general? In spite of being a doctor, he definitely lacked bedside manner. Did he just not wish to appear crippled in front of people? Was he simply tired of dealing with humanity? She'd known her share of curmudgeon doctors in her education so far, and that answer still didn't quite seem to fit. None of them had gone so far as to exile themselves to a barren, lonely existence in an abandoned building.

Now that she thought about it, she remembered a point from her research on Dr. Carter. By the terms of his will, the same terms that stated that the old building was to be maintained but not used, his office was also to be kept locked and never entered. It was the one place in that building least susceptible to detection. If the Maestro wanted a hideout, he had picked a spectacular one.

But why? And he was lonely. The pain in his eyes and voice was much more than merely physical. Why shut himself off from the world? Why restrict his access to the medicine that he clearly loved, the puzzles if not the people?

She went to bed late, slept badly, and apologized to James Wilson the next morning, just saying that something urgent had come up. He accepted the excuse with an easy grace, commenting that doctors of course had that happen all the time, so it was bound to occur on occasion. His lack of resentment made her feel even more guilty for silently consenting to the misconception that whatever had come up had been a patient.

Cuddy did go out with him the next evening, and he was the perfect date: Charming, attentive, romantic. She could indeed unbend a little and enjoy herself, she realized. When Wilson wanted to set up a repeat, she didn't object.

She didn't hear anything from the Maestro for a few days, although she tried walking around the roof and calling him. She also purchased a few small food items beyond peanut butter or ham sandwiches, though she included at the last moment a Big Mac, carefully wrapped with extra insulation to keep it hot. She also included a packet of stick-on heat packs. She debated long before putting that last item in and nearly took it out anyway. She didn't want him to think she was just focusing on his leg. Finally, she wrapped her gift pack in a jacket for padding (though it was a jacket that would fit him) and tossed it lightly over the fence. She then left the roof, and when she came back an hour later, the bundle was gone.

It was three days after her visit to his lair that one of the attending doctors was out sick. Since another of the attendings was already on vacation, this left the hospital a little short handed, and in response, they called on an older doctor she hadn't met yet, one apparently nominally retired but still providing an extra set of licensed hands with the patients at PPTH in a pinch.

Dr. Nordstrom was old and bushy, with a wild mustache below twinkling eyes. Add a beard, and she could see him playing Santa Claus. He led them through rounds and discussion of all current patients, and he was obviously competent, the sort of steady, routine, soothing doctor that most patients probably enjoyed. He was just as plainly loving getting back into harness, even if only temporarily. After the morning's rounds, he came up alongside Cuddy as the other residents dispersed.

"Well done, Cuddy, well done!" he told her. "You keep it up, and you're going to make an excellent doctor. You have a refreshing way of trying to think of other possibilities, not just the obvious ones."

"Thank you," she replied.

"Yes, indeed, you have a lot of promise. A few of your comments almost reminded me of a fellow I knew a long time ago." His eyes refocused on the past. "I've never forgotten him. Now he would have been spectacular. He had the same trick of thought but was even better than you at it. You had to work, were obviously pushing yourself today. He just naturally seemed to have other possibilities occur to him. What a mind he had!"

Cuddy tried not to show how much this old doctor now had her attention. Of course, this might be coincidence, but if so, it was a major one. "Where is he practicing now?" she asked, deliberately casual. "If he had that good a mind, he must have gone on to great things."

Dr. Nordstrom pulled himself up in mid reminisce. "He . . . developed some health issues and other problems," he stated sadly. "He never finished study."

Cuddy shook her head. "Sounds like he was a great loss to the medical world. Couldn't he still have been a research doctor or something, even if he couldn't actively work because of his health?"

"No, that . . . the whole situation was very unfortunate . . . he left medicine."

"What was his name?" Cuddy asked. He looked at her oddly. "I just wondered if anyone else here has ever mentioned him."

"I doubt it," Nordstrom replied. "There are some staff still here who knew him, but very few who miss him. Most were quite happy to be allowed to forget him." He looked beyond her into the past again and sighed. "His name was House. Gregory House."

Was. "Is he dead?" Cuddy asked. She had never heard of a Dr. Gregory House.

Dr. Nordstrom came to attention. "I really must be getting on to lunch now. Thank you for a pleasant morning, Cuddy. Keep up the good work." He turned and left.

Cuddy stood there in the hallway so long that another resident passing by finally waved a hand in front of her face. "Hello? Anybody home?"

"Just thinking," Cuddy replied. She turned quickly and headed for the doctor's lounge. She had been hungry five minutes ago, but now she had an appetite for information, not food. Settling down at one of the computers there, she started digging through old medical databases and PPTH rosters.

Gregory House. He had been a fellow at PPTH until 10 years ago. His career had ended abruptly in his third year of fellowship, and then, as far as medical databases were concerned, he seemed to have dropped off the face of the earth.

If the Maestro and Dr. House were the same, could he possibly have been in self-imposed prison over there alone in pain for 10 years? Nordstrom had mentioned health problems, but those, of course, were not itemized in the professional databases.

Wait a minute. Nordstrom hadn't just mentioned health issues. He had added "other problems" to that list. Non medical problems?

On a long shot, she ran a search in general public sources, not limiting it to medical sites, and a few minutes later, she was staring at the computer screen, eyes wide, mind whirling.

He not only had developed health problems. He also was apparently wanted for questioning in a murder.