Author's Notes: This chapter is a bit short but I wanted to get it out before I head back out to sea again. It gets the story moving along once again. Hopefully, I'll have a chance to write while I'm gone, and will have another update when I return. Enjoy!

0530, October 3, 2552, Local Time
Corridors, Echoes of Eternity

They found Sergeant Harris a few minutes later, sitting with his back against the airlock door behind which the rest of his fire team had been trapped. He was staring blankly at the far bulkhead, silent, surrounded by empty battle rifle and pistol magazines. Behind him, the metal alloy door was pocked and scored from hundreds of hits, but the damage was little more than cosmetic. He'd expended every round of ammunition he had, and it hadn't made a difference.

John approached slowly, recognizing that the Sergeant could be in an unsteady state of mind. Watching friends die did things to any person's head. Harris didn't even look up at him as he stood over him. He started toward the airlock view port.

"Don't bother," Harris said suddenly, quietly. "Nothing but corpses in there."

John looked anyway. As he'd expected, the four Marines inside were dead, suffocated in a matter of moments. Private First Class Amanda Kadee hadn't even fallen. She was on her knees, head bowed as if in prayer, her battle rifle clutched in both hands… still covering the far exit as ordered.

But just as Harris has reported, before the airlock doors had started closing, there were also the bodies of several dead Covenant inside. It looked like they had died the same way.

Cortana came to the same conclusion he did. "I'm not so sure the Covenant have control of their own AI right now," she said quietly, on his private comm channel. "She must be in some kind of self defense mode, but she can't tell friend from foe. Who knows how many other traps like this one are onboard, just waiting for someone to stumble into them? Are we still sure we want to bring this thing back with us?"

"We've got our orders," John said simply. He reached down to pat Harris on the shoulder. "Let's go."

Just as the Sergeant started to stand, the airlock door's seal disengaged with a hiss of lost vacuum, and slid upward into the overhead. Harris just stood there for a moment, then started toward his fallen fire team.

"Wait," the Spartan said, stopping him in his tracks. "She's just setting the trap again."

Harris looked at him in confusion.

"Eternity has probably been programmed to recognize human behavior," he explained. "She knows we go back for our dead." He nodded toward the dead Marines. "She wants us to go in there and try to get them out… so that she can seal us in and kill us, too."

At first, he thought the Sergeant was going to protest, but then he just nodded, picked up his battle rifle, and dropped the empty clip. "I'm going to need some ammo."

Even after finding their way back to their original route, the Master Chief knew that the loss of Echo Team was going to continue to slow them down. Now that they knew the ship was booby trapped, they'd have to step extra carefully, double checking even innocuous looking bulkheads and hatches, just to make sure they couldn't be turned into some sort of weapon by the wayward onboard AI.

As they progressed deeper and deeper into the ship, they found more and more bodies. It was quickly becoming clear that the Covenant were fighting their own ship as much as they were the Humans. Some of the dead aliens had been suffocated like the first group; others had been electrocuted, and a few had even been killed by what looked like friendly fire - no doubt cut down by panicked comrades blazing away in a haze of unreasoning terror. The Master Chief had seen a lot of things in his lifetime, but something that could stop a fully armed and armored Elite dead in its tracks in a matter of seconds sent a chill down even his spine.

"So what now?" Mitchell voiced over the comm the question that all of them were thinking. "If the AI is trying to kill them, the Covenant probably aren't going to be protecting her central location. So how do we find it?"

"Well, we can't go based off of where the Covenant aren't hanging out," Avery put in. "Eighty percent of the ship must be abandoned."

"Abandoned, and badly damaged," John said. "In order to survive and function properly, Eternity needs power. She'll be cutting off power to systems and sections of the ship that she doesn't need or can't use. Cortana, if I plug you into a data terminal, can you trace where the power relay commands are originating from?"

"I'll probably have to hack through some defenses," the AI replied thoughtfully. "And there's no guarantee that she won't be able to back trace my access. But it's worth a shot. It's either that, or we can keep wandering around this deathtrap all day."

"All right," John said, "all fire teams hold position and take cover. Once we have some results, I'll have further orders." He waited until the other teams acknowledged, then started looking for a data terminal. He found one in a service corridor a few minutes later. He posted the members of his team to cover him while he got Cortana plugged in. "Is it even active?" he asked after a moment.

"Thank the stars for small miracles," she replied wryly. "At least I'm getting some sort of data flow here. She apparently didn't think this console was worth locking down. It's function is relatively minor though, and it's not designed to have access to most of the ship's major systems. It'll take me a few moments to even access the mainframe."

"We need that information," he reiterated. "Do what you have to."

It took her nearly a full minute, which was, for Cortana, a long time. "Got it," she said finally. "Mainframe access." She paused. "As I suspected, she's got defenses and traps set up everywhere. She abandoned all the files and programs for peripheral and nonessential systems, and locked down everything from weapons and life support to communications and sensors. All manual controls and systems have been overridden and locked out. She's definitely in self-preservation mode, big time."

"Can you figure out where she's at? Or at least pinpoint a location where we could download her program, or a copy of it?"

"I'm setting up query programs right now, to see if I can trace her command routes. I can try to be stealthy, so she doesn't realize I'm in here looking for her, but it will take several minutes, at least. Or I can be quick and dirty, but she'll know what we're up to in a matter of seconds."

John thought over the options. The success of their original plan had depended on their speed, and they'd been significantly bogged down. Finding Eternity's location quickly was definitely appealing, but the situation had changed dramatically. The Covenant knew they were aboard. So did Eternity, but unlike the Covenant, she probably didn't know why. If they could keep her in the dark until it was too late for her to defend against a download, that would eliminate a major headache.

"Take the stealthy route," he ordered.

"Copy," she replied. "Here goes nothing."

And that was it. John could do nothing but wait. It was his least favorite part of any mission: sitting back and waiting for someone else to do the work. But there were none better than Cortana for something like this, and he just had to trust that she could get the job done.

"She's on to me!" Cortana exclaimed suddenly on a few seconds later. "She's faster than I predicted!"

John tensed a bit, leaning over the console as if he could will Cortana to win the virtual battle that was suddenly erupting. "Do you have a location yet?"

"Negative!" the AI replied, and the Master Chief noticed with a bit of concern that her voice actually sounded stressed. "My query programs are less than ten percent complete! She's trying to isolate them and overwrite them. She… she's trying to infect my programming with viruses!"

"That's it, I'm pulling you out," he said.

"No! I can get it! A few more seconds!"

From the sounds of it, John was going to have to buy her those seconds. He thought fast. "Mitchell!" he barked over the Marines' comm channel. "Find something important looking and blow it up, now! That goes for all fire teams!"

"Chief?" Mitchell started to ask.

"She's running too many subroutines!" he vaguely heard Cortana exclaiming. "She's erasing my queries; I can't stop them all!"

"Just shoot something!" he ordered Mitchell.

There was no verbal response. The deck beneath him shuddered almost imperceptibly, then again, harder this time, as grenades and shaped charges started exploding. He could almost imagine the Marines a few levels below him, throwing ordnance in every direction.

He suddenly realized that Cortana had fallen silent. "All teams, hold fire," he said. The cacophony beneath him abruptly faded away. "Cortana?"

For a moment, there was silence. "'Just shoot something,' huh, Chief?" the AI said wryly. "Crude, but effective. Eternity was distracted just long enough for me to get the edge."

"And?" he prompted.

"I found her."