Cale and Jak nodded a greeting, and Riven returned the gesture.

"Anything?" the assassin asked.

"All quiet," Cale replied.

"Too bad," said Riven, and the three shared a chuckle.

Rotating one man out for breaks, they sat atop the rowhouse while the sun set, night fell, and Selune rose. As Cale had suspected, nothing happened. At midnight, Cale sat apart from Riven, regularized his breathing, closed his eyes, and silently prayed to Mask for his spells. The Lord of Shadows heeded Cale's request, and the holy words burned themselves into his brain, words of power that Cale could actuate with his will and his holy symbol. He felt Riven's gaze on him throughout, but they didn't speak of it afterward.

Otherwise, the night passed with nothing more interesting occurring in the street below than a carriage throwing a wheel. Each of the three managed to get at least a few hours of sleep.

The next day, the gongs and bells of the Temple District sounded the dawn and began to count down the hours. Sephris had told them to return in eighteen hours—not tomorrow afternoon or evening, but exactly eighteen hours. Cale figured that Sephris meant what he said. They would return between the fourth and fifth hour.

Like the night, the day passed without incident. The caretaker-priest exited Sephris's home in the morning to retrieve two buckets of water from a nearby city well.

Otherwise, they saw nothing but the occasional passerby. The time passed—slowly, but it did pass.

About half an hour after the Temple of Song rang the fourth hour, Cale stood.

"Let's move," he said to Riven and Jak.

The three descended the row house on the alley side and hit the street. As before, the caretaker-priest, dressed in green robes, opened the door to Sephris's house before they reached the porch. Cale figured he must have some kind of alarm spell triggered by the opening of the wrought iron gate.

"Gentlemen," the priest said, managing to inflect the word just enough to make it an insult. "Sephris is expecting you. He has been awake all night." From the circles under the priest's eyes, Cale thought that he too had probably been up all night. "Follow me," he said.

Riven grabbed Cale's shoulder and said, "I'll wait."

"What? Wait?" asked Jak.

Ignoring the halfling, Riven kept his gaze on Cale.

"I don't care what the sphere is," the assassin said. "You know my terms."

Cale looked into Riven's face. Indeed he did know Riven's terms—the death of Vraggen—but he also knew the real reason for Riven's reluctance to enter the house: Sephris made him uncomfortable. No reason to make an issue of it. He gave Riven an out.

"That's a good thought. Watch the street in case anyone else shows."

Riven nodded.

Cale and Jak turned to follow the priest. As he walked, Cale realized that he was beginning to regard Riven as something more than an assassin. He was beginning to regard him as a man, with human weaknesses and fears. That made him uneasy. It could make hard decisions more difficult if their relationship went bad later on. He put it out of his mind as they entered Sephris's house.

New formulae covered the plaster walls of the hallway. To Cale, they looked hurried. Sephris's precise script had given way to a barely legible scrawl, as though the thoughts had come too fast for his hands to record.

"As you can see," the priest said, "Sephris has been very busy since you left."

Cale nodded. He and Jak shared a pensive look.

The priest led them to the library doors. Before he opened them, he turned to face them, lips pursed.

"I fear that your perception of what is happening here, with Sephris, may be ... incorrect."

Jak began to interrupt with a protest but the priest held up a hand and cut him off.

"I can see it in your face. To someone from outside the church, it may appear that we treat Sephris as an oddity, or perhaps a sort of mascot."

Here he looked at Cale with hooded eyes. Cale managed to hold his gaze, though his thoughts tracked the priest's words. It seemed to him that Oghma's church displayed Sephris the same way a Cormyrean sideshowman displayed his freaks. That the church required a "donation" to see Sephris only solidified the perception.

The priest gave a tight smile and nodded, as though he had read Cale's thoughts.

"I assure you that is not the case," the priest continued. "Without a caretaker, Sephris would not eat, drink, or bathe. Caring for him is not always pleasant, yet my brethren and I regard it as an honor."

"An honor?" Jak exclaimed. "I thought—"

"You were mistaken," the priest interrupted. "You see, Sephris is not insane. He is blessed, one chosen by the Lord of Knowledge, and is so regarded by all in Oghma's orthodox church."

Disbelief must have shown on Cale's face.

The priest nodded. "I know how it must appear to you, but it is not so. Oghma has blessed Sephris with a unique gift—an ability to think in a way that no one else can think, to know what no one else can know." Sadness, or awe, dropped the priest's voice. "It is a wondrous gift, but a gift from a god can be a difficult burden for a man to bear." The priest looked at them and gave a soft smile. "Such is the case with Sephris."

The priest seemed to be waiting for a response. Cale could think of nothing to say. He didn't know why the priest had just told them what he had. He merely nodded.

The priest looked from one to the other, his face emotionless, then he turned and opened the doors. As he did so, his words stuck in Cale's brain: Sometimes a gift from the gods is a difficult burden for a man to bear. Cale reached into his vest pocket for his holy symbol but stopped before touching it.

"Sephris," the caretaker-priest said, "the petitioners from yesterday have returned."

The priest turned and nodded to Cale and Jak, then exited the library, pulling the doors closed behind him.

To Cale, the library appeared even more disorderly than it had the day before. Papers and workslates lay strewn about everywhere, all covered in Sephris's urgent scrawl. On the desk, set upon a stack of papers, stood an intricately crafted bronze orrery. Beside it sat the half-sphere. Sephris hovered over both, staring. He looked the same. He hadn't changed his red cloak and Cale doubted that he had eaten. Despite the frantic nature of Sephris's writings, the man himself appeared calm and composed, at least at the moment. Cale supposed that even those fueled by divine knowledge could not maintain a fervor forever.

Without looking up, Sephris said, "Only two of the three on this seventeenth day of the sixth month."

"Sephris?" Jak asked hesitantly. "Are you all right?"

Sephris looked up. Dark circles colored the skin under his eyes.

"Indeed, Jak Fleet. Better than I have been in some time." He put his hand on the half-sphere and grinned. In that smile, Cale saw madness, or conviction. "I can't see it," Sephris continued. "It is a dominant variable, but so dominant that I don't know. I cannot solve it."

Cale's heart sank as the import of those words registered. Sephris didn't know what the sphere was. They had wasted a day.

"Come here," Sephris said, and waved them toward the desk.

Cale and Jak walked across the library, each careful to avoid stepping on any of Sephris's work papers.

"Never mind those," Sephris snapped. "Come here."

The half-sphere sat on the desk, inert, inscrutable even to Oghma's Chosen. Cale stared at it. He didn't know what he would do next.

Sephris smiled at them. His eyes were bloodshot and intense. His hair stuck up at odd angles. He nodded at the half-sphere.

"I cannot solve it! You have presented me with a premise for which I cannot craft a proof. For that, I thank you."

"Thank us?" Jak asked.

Sephris nodded and said, "Indeed. I have thought for some time that there was nothing that I could not solve, given time. I am pleased to be wrong."