Cortana spun around and her eyes widened. “They approved the final phase?”

“Is it possible, Cortana,” Dr. Halsey replied, amused, “that I know something you don’t?”

Cortana wrinkled her brow in frustration, then smoothed her features to their normal placid state. “I suppose that is a remote possibility. If you’d like, I can calculate those odds.”

“No, thank you, Cortana,” Halsey replied.

Cortana reminded Dr. Halsey of herself when she had been an adolescent: smarter than her parents, always reading, talking, learning, and eager to share her knowledge with anyone who would listen.

Of course, there was a very good reason why Cortana reminded Dr. Halsey of herself.

Cortana was a “smart” AI, an advanced artificial construct. Actually, the terms smart and dumb as applied to AIs, were misleading; all AIs were extraordinarily intelligent. But Cortana was special.

So-called dumb AIs were engineered to function only were misleading; within set limits of their dynamic memory-processing matrix. They were brilliant within their fields of expertise, but were lacking in “creativity.” Déjà, for example, was a “dumb” AI—incredibly useful, but limited.

Smart AIs like Cortana, however, had no limits on their dynamic memory-processor matrix. Knowledge and creativity could grow unchecked.

She would pay a price for her genius, however. Such growth eventually led to self-interference. Cortana would one day literally start thinking too much at the expense of her normal functions. It was as if a human were to think with so much of his brain that he stopped sending impulses to his heart and lungs.

Like all the other smart AIs that Dr. Halsey had worked with over the years, Cortana would effectively “die” after an operational life of seven years.

But Cortana’s mind was unique among all the other AIs Dr. Halsey had encountered. An AI’s matrix was created by sending electrical bursts through the neural pathways of a human brain. Those pathways were then replicated in a superconducting nano-assemblage. The technique destroyed the original human tissue, so they could only be obtained from a suitable candidate that had already died. Cortana, however, had to have the best mind available. The success of her mission and the lives of the Spartans would depend on it.

At Dr. Halsey’s insistence, ONI had arranged to have her own brain carefully cloned and her memories flash-transferred to the receptacle organs. Only one of the twenty cloned brains survived the process. Cortana had literally sprung from Dr. Halsey’s mind, like Athena from the head of Zeus.

So, in a way, Cortana was Dr. Halsey.

Cortana straightened, her face eager. “When does the MJOLNIR armor become fully operational. When do I go?”

“Soon. There are a few final modifications that need to be made in the systems.”

Cortana leaped to her “feet,” turned her back to Dr. Halsey, and examined the photographs on the wall. She brushed her fingertips over the glass surfaces. “Which one will be mine?”

“Which one do you want?”

She immediately gravitated to the picture in the center of Dr. Halsey’s collection. It showed a handsome man standing at attention as Admiral Stanforth pinned the UNSC Legion of Honor upon his chest—a chest that already overflowed with citations.

Cortana framed her fingers around the man’s face. “He’s so serious,” she murmured. “Thoughtful eyes, though. Attractive in a primitive animal sort of way, don’t you think, Doctor?”

Dr. Halsey blushed. Apparently, she did think so. Cortana’s thoughts mirrored many of her own, only unchecked by normal military and social protocol.

“Perhaps it would be best if you picked another—”

Cortana turned to face Dr. Halsey and cocked an eyebrow, mock stern. “You asked me which one I wanted... .”

“It was a question, Cortana. I did not give you carte blanche to select your ‘carrier.’ There are compatibility issues to consider.”

Cortana blinked. “His neural patterns are in sync with my mine within two percent. With the new interface we’ll be installing, that should fall well within tolerable limits. In fact—” Her gaze drifted and the symbols along her body brightened and flashed. “—I have just developed a custom interface buffer that will match us within zero point zero eight one percent. You won’t find a better match among the others.

“In fact,” she added coyly, “I can guarantee it.”

“I see,” Dr. Halsey said. She pushed away from her desk, stood, and paced.

Why was she hesitating? The match was superb. But was Cortana’s predilection for Spartan 117 a result of him being Dr. Halsey’s favorite? And did it matter? Who better to protect him?

Dr. Halsey walked over to the picture. “He was awarded this Legion of Honor medallion because he dove into a bunker of Covenant soldiers. He took out twenty by himself and saved a platoon of Marines who were pinned down by a stationary energy weapon emplacement. I’ve read the report, but I’m still not sure how he managed to do it.”

She turned to Cortana and stared into her odd translucent eyes. “You’ve read his CSV?”

“I’m reading it again right now.”

“Then you know he is neither the smartest nor the fastest nor the strongest of the Spartans. But he is the bravest—and quite possibly the luckiest. And in my opinion, he is the best.”

“Yes,” Cortana whispered. “I concur with your analysis, Doctor.” She drifted closer.

“Could you sacrifice him if you had to? If it meant completing the mission?” Dr. Halsey asked quietly. “Could you watch him die?”

Cortana halted and the processing symbols racing across her skin froze midcalculation.

“My priority Alpha order is to complete this mission,” she replied emotionlessly. “The Spartans’ safety as well as mine is a Beta-level priority command.”

“Good.” Dr. Halsey returned to her desk and sat down. “Then you can have him.”

Cortana smiled and blazed with brilliant electricity.

“Now,” Dr. Halsey said, and tapped on her desk to regain Cortana’s attention. “Show me your pick of our ship candidates for the mission.”

Cortana opened her hand. In her palm there was a tiny model of a Halcyon-class UNSC cruiser.

“The Pillar of Autumn,” Cortana said.

Dr. Halsey leaned back and crossed her arms. Modern USNC cruisers were rare in the fleet. Only a handful of the impressive warships remained... and those were being pulled back to bolster the defense of the Inner Colonies. This junk-heap, however, was not one of these ships.

“The Pillar of Autumn is forty-three years old,” Cortana said. “Halcyon-class ships were the smallest vessel ever to receive the cruiser designation. It is approximately one-third the tonnage of the Marathon-class cruiser currently in service.

“Halcyon-class ships were pulled from long-term storage—they were designated to be scrapped, in fact. The Autumn was refit in 2550, to serve in the current conflict near Zeta Doradus. Their Mark Two fusion engines supply a tenth of the power of modern reactors. Their armor is light by current standards. Weapon refits have upgraded their offensive capabilities with a single Magnetic Acceleration Cannon and six Archer missile pods.

“The only noteworthy design feature of this ship is the frame.” Cortana reached down and pulled off the skin of the holographic model as if it were a glove. “The structural system was designed by a Dr. Robert McLees—cofounder of the Reyes-McLees Shipyards over Mars—in 2510. It was, at the time, deemed unnecessarily overmassed and costly due to series of cross-bracings and interstitial honeycombs. The design was subsequently dropped from all further production models. Halcyon-class ships, however, have a reputation for being virtually indestructible. Reports indicate these ships being operational even after sustaining breaches to all compartments and losing ninety percent of their armor.”