Outside the door, it sounded as if Olivetti, the camerlegno, and Captain Rocher were debating what to do next. Apparently, the antimatter search had turned up nothing so far. Either the guards had missed the canister, or the intruder had gotten deeper inside the Vatican than Commander Olivetti had been willing to entertain.

Robert Langdon staggered into the private bathroom adjoining the Office of the Pope. He dabbed the blood from his face and lips. The blood was not his own. It was that of Cardinal Lamassé, who had just died horribly in the crowded square outside the Vatican. Virgin sacrifices on the altars of science. So far, the Hassassin had made good on his threat.

Langdon tried to rid his mind of the bloody brand he had just seen. Air. The image stuck. He had witnessed three ambigrams since waking up this morning… and he knew there were two more coming.

Langdon felt powerless as he gazed into the mirror. His eyes were drawn, and stubble had begun to darken his cheeks. The room around him was immaculate and lavish -- black marble with gold fixtures, cotton towels, and scented hand soaps.

Langdon dried his hands and face. Then he turned and looked for a urinal. No urinal. Just a bowl. He lifted the lid.

Think, he told himself. His mind was blank.

As he stood there, tension ebbing from his body, a giddy wave of exhaustion shuddered through his core. The emotions knotting his chest were so many, so incongruous. He was fatigued, running on no food or sleep, walking the Path of Illumination, traumatized by two brutal murders. Langdon felt a deepening horror over the possible outcome of this drama.

As he flushed, an unexpected realization hit him. This is the Pope's toilet, he thought. I just took a leak in the Pope's toilet. He had to chuckle. The Holy Throne.