"So this is what happens if you tread on the cracks," she said.

Mendez stared at the flagstones. They'd come alive with pulsing illuminated symbols. A straight line of Forerunner glyphs, picked out in a soft blue light, led along the paving and curved up the wall to waist height. Halsey walked along the line. For all Mendez knew, it could have been a warning to keep clear. They'd find out the hard way.

"Can you read that?" he asked.

"It's a sequence of numbers," Halsey said. "But beyond that-no idea."

She reached out and touched the top symbol. Nothing happened for a few moments, but then Linda and Fred swung around ready to open fire as if they'd heard something that Mendez hadn't. He looked back at Halsey just as the wall above him split along a neat vertical line and parted all the way down to the ground. Nothing actually moved; the stone blocks just suddenly vanished. In his world, doors that suddenly flew open tended to spew small-arms fire.

The Spartans split instantly into two groups without a word and stacked either side of the opening, rifles ready. Halsey froze. Mendez reminded himself to give her his pistol.

"Steady..." Fred said. "Check first. Shoot later."

Mendez moved around to face the opening head-on. He could see movement in his optics and his finger began tightening on the trigger. Then the movement resolved into gliding gray cylinders like the one that had swooped on them earlier. There were six this time. They moved out of the opening and arranged themselves along the wall at head height. Mendez wasn't sure if they could detect weapons, but they didn't seem to be making any defensive moves.

"So what are you?" Halsey murmured. One cylinder separated from the rest and came to a halt just in front of her face. To her credit, she didn't even blink. "What are you monitoring? That's what you're doing, isn't it?"

The cylinder moved from Halsey to Mendez, hovering so close that he felt it was staring into his eyes even though he couldn't see a single damned detail on it. He held his breath until it moved away, smooth and silent, to hover in front of Kelly's visor. She stood motionless with her rifle in one hand. Then she grabbed it, as fast as a chameleon ambushing a fly. It was so quick that Mendez didn't even have time to flinch.

"Gotcha," she said, peering at it.

The cylinder didn't seem to be struggling. The other cylinders drifted away into the trees as if they had better things to do than hang around amusing humans.

"It feels like it's not here. It doesn't weigh anything." Kelly flexed her gloved fingers around it. "Wow. This is the strangest thing I've ever felt."

Halsey held her hand out and took the cylinder cautiously. She drew her chin in, frowning. "I see what you mean. That's ... well, extraordinary. Better hope I'm right and that it's just some kind of recon drone."

Mendez resisted the urge to touch it and see what all the fuss was about. "We're still making a lot of assumptions, Doctor."

"Forerunner technology can recognize humans. So I'd call it an educated guess."

Lucy peered around the opening in the wall and Mendez gestured to her to cover him while he checked inside. He couldn't see anything. Then the whole damn interior lit up like Christmas, flooding the walls with lights and symbols from waist height to about five meters, reminding him of the control room of a power station. But it was completely, eerily, silent.

Lucy, just as silent, explored the chamber. It was about thirty meters wide but Mendez couldn't see a ceiling in the gloom above. When he glanced back over his shoulder, Fred and Kelly were in the doorway, silhouetted against the daylight.

"There's no way we can jam this open if it decides to shut," Fred said.

Mendez felt they didn't have much choice but to explore the place. "We'll have to take our chances."

Then Lucy grabbed his forearm so hard that it hurt. He spun around. She made a shut-up gesture, finger to lower third of her visor, and pointed into the shadows on the left. The poor kid hadn't spoken a word for eight years. But he knew how to listen to her. He held up a hand to stop everyone and edged forward.

Maybe she'd picked up something in her infrared filter. He still couldn't see anything. But then he heard it.

Something was moving away from them. It wasn't a cylinder. It sounded like wet leather slapping against stone followed by the clatter of metal, getting fainter and almost echoing. Something was moving down a passage. The sound died away into silence again.

Mendez nodded at Lucy. Halsey crept up to him, ignoring the order to stay put, still clutching the cylinder.

"What is it?" she asked.

"No idea. But that didn't sound like the central heating boiler to me."

"But we were the first in here. We activated the core room."

"No, we just found a way in." Mendez checked his ammo clip and headed into the shadows, stomach knotted tight. "But someone else found it first."

UNSC PORT STANLEY, MIDPOINT ANCHORAGE, TEN MINUTES BEFORE JUMP TO SLIPSPACE: JANUARY 27, 2553.

Osman tried the CO's seat on the bridge and felt small and alone. She hadn't expected that. It certainly didn't give her a thrill.

I've always been a spy in a blue suit.

She'd never felt like a real naval officer. ONI had taken custody of her as a fourteen-year-old, educated her, put her through the ONI commanders' program, and reinvented her. She'd deployed in ONI's fleet before, but she'd never had day-to-day command of a ship. Now she was going to find out the hard way if she could cut it.

Well, Parangosky thinks I can....

"In case you're interested," BB said, "I'm doing the final launch checks. Would you like me to spell them out?"

Osman couldn't see him. She stared straight ahead at the disc of Mars, a small rusty smudge framed in light-speckled blackness in the forward viewscreen. "I trust you, BB." He could have left it all to the dumb AI, of course. "Where is everybody? Secure for launch."

"The ODSTs are in the wardroom. They're very excited about having their own cabins. I can tell from their bio signs. Poor little waifs."

"Don't stalk them, BB. It's creepy."

"Just monitoring, Captain. And Phillips is checking out the crates in the cargo bay. I think reality has dawned on him. Are you happy having him embarked?"

"Not really. Opsec worries."

"All comms go through me, Captain."

"I meant when we get back."

"Oh, I'll guarantee his silence. One way or another."

"I'll bet."

Osman suddenly needed something to focus on. She turned around in her seat because BB's voice felt as if it was coming from behind her. He was, of course, everywhere at once; he was in every part of the ship's systems, observing via every monitor and camera, controlling every aspect of its operation, in touch with Earth and able to hear and respond to any callsign in the galaxy, omniscient and omnipotent-for the few years he had to live, anyway. An AI was a short-lived god. When she turned back to face forward, BB materialized a meter in front of the bulkhead.

"And where's Naomi?" she asked.

"Heading this way," BB said. "You might as well tell her."

The Spartan had been giving Osman odd looks all the way out here in the shuttle. Naomi seemed to realize she knew her but couldn't place the face. Osman thought she'd changed a lot since her early teens, but some features didn't alter with age.

"Yes, we've already got enough secrets to keep from one another." Osman got up and stood facing the doorway onto the bridge, resting her backside on the comms console. "I'll tell the others too. If we're running arms for Sangheili psychos, I suppose my status pales into insignificance. No reason why I can't, is there?"

BB moved around to settle in her line of sight. "The Admiral gave you carte blanche. Weapons free, repel all boarders, no prisoners, et cetera et cetera. Do whatever you need to get the job done ... just don't get caught, there's a dear."

BB had a rather arch way with him. Osman found herself smiling. Dear. Things were going to get very informal. She could hear Naomi coming now, the steady thud of her boots on the deck as she strode along the passage in that massively heavy armor she didn't actually need at the moment. Spartans had their comfort blankets too.

How would I have coped with the Mjolnir? Would I feel naked without it? Would I know where I ended and it began?

Naomi loomed in the doorway. She had that faint frown that said a memory was still eluding her. "Ready to slip, ma'am?"

"Five minutes." Osman realized BB had disappeared, or at least his avatar had. "Anything you want to ask me, Naomi?"

Using her name rather than addressing her as Spartan got a slight reaction. Osman noted a couple of rapid blinks.

"Yes, ma'am," Naomi said at last. "I think I know you, but I don't know where from."

"It's been a long time. And my name wasn't Osman back then. Like you, I didn't even have a surname."

Osman had rarely come face-to-face with Spartans from her batch. On the handful of occasions when she had, she found they were pretty good at forgetting because they'd been made to forget so much. She concentrated on Naomi's pale gray eyes, searching for the moment the penny dropped. The Spartan had now stopped blinking completely.

Naomi struggled with the name. "Sarah?"

"Serin. Serin-Zero-One-Nine. Remember me now?"

As Osman watched the revelation build on Naomi's face, she felt the tension drain from her own shoulders. The relief was both unexpected and incredible. She hadn't realized she'd been that worried about it.

But it's out. Thank God for that. Someone other than me and the select few in ONI knows who I am.

Nearly half of the seventy-five children who'd been taken for the program didn't make it past augmentation treatment at fourteen. The few who didn't die were left disabled. Osman didn't know what Halsey had actually told her successes about the fate that had befallen her failures.

"We thought you'd died," Naomi said.

Well, that answered Osman's question. "I did, near as damn it. ONI put me back together again, so now you know. And don't tell me how normal I look. I still have some enhancements, but nothing skeletal."

All Osman had needed was to see the look on Naomi's face. It was a kind of validation. She'd been wiped out of existence twice, first as a kidnapped kid taken to Reach, then erased from the Spartan program, but now nobody could erase her again.

I exist. I'm here. And I'm going to head up ONI.

Naomi settled at one of the comms stations and secured the seat belt as if nothing had happened. "We'd better get going, ma'am."

Osman wasn't sure if the subject was closed or not. If it wasn't, it would have to wait. She was about to summon the ODSTs when they arrived on the bridge with Phillips and BB. All three of them-even Devereaux-stood at ease looking like everyone's worst nightmare; unsmiling, unblinking, and silent. Mal and Vaz had do-not-spill-my-beer written all over them. It was partly the buzz-cut hair and complete absence of expression, but also ... damn, Osman couldn't quite pin it down. Whatever it was, she was sure she could pick an ODST out of a lineup every time, male or female. It was that earnest hardness, that sense that they would do absolutely anything they were tasked to do, however insane or impossible, and that once they were let off the leash only shooting them would stop them.

"Cabins okay?" she asked.

Mal thawed a little. His file said he was thirty-three but he looked younger, with a fuzz of dark hair and just a few lines around the eyes that suggested he actually spent a lot of time laughing. Vaz-ho managed to look both time-worn and twenty-something at the same time-had one of those lean, high-cheekboned Slavic faces and a spectacular scar the full width of his jaw. He didn't seem the laughing kind at all.

"Brammers, ma'am," Mal said, deadpan. Osman assumed from his tone that it was high praise. "We never normally get a pit to ourselves. Vaz is delirious about it. Honest."

"I'll take your word for it." The only problem with drawing ODST recruits from all nations and all three services was that many of them were completely unintelligible even in English. It was part of their curious charm. "There's a set of upgraded recon armor for each of you, too."

"Thank you, ma'am. Luxury."

"Okay. Secure for launch. BB, you have the ship."

Phillips never said a word as he buckled in. Osman caught his eye. If anything, he looked amused, as if she hadn't fooled him at all about what ONI was actually up to.

BB appeared settled on the console in front of her. "Thirty seconds ... receiving final updates ... you could have sedation, you know."

Osman couldn't hide a thing from him. She knew she'd kissed good-bye to privacy before she was even old enough to understand what it was, but an AI could know more about someone than their own mother. Protective or not, it rattled her. BB had access to every cockpit recording and medical report, and he could probably pick up her pulse rate, too, the intrusive little bastard.

She heard one of the ODSTs trying to stifle a yawn. Nothing fazed them. Port Stanley's drives rose from a faint whine to what she could only describe as an intense nonsound that made her brain feel like it was being sucked down her Eustachian tubes.

It was too late to stop. The drives were spooled up and committed to jump now. "I can deal with it," she said.

"Late databurst incoming ... never mind, that'll have to wait ... five seconds." BB executed a smart one-eighty-degree spin. "Place your bets on where and when we emerge, ladies and gentlemen ... and jump."

Osman never looked at the external view. She couldn't. Her gut plummeted and went on falling. Her brain told her she was tumbling head over heels down an unending tunnel, even though she could see her own fingers digging into the padded black armrests of her chair. Her eyes flickered uncontrollably as they tried to make sense of the misleading impulses from her brain. She was falling, completely out of control, and that was all there was to it. The sickening sensation behind her eyes crept down her neck and made her hunch her shoulders.

Then she hit a brick wall. For a moment she was swaying horizontally on a storm-tossed deck, and then everything slowed to a stop. Throwing up wasn't a very captainly thing to do. She gritted her teeth and waited for it to pass.

She must have sat there longer than she realized. One of the ODSTs leaned over her.

"You okay, ma'am?" Devereaux asked.

Osman made an effort to stand up and look vaguely in command. "Jumps don't agree with me."

"Like Nelson. Never did his reputation any harm, though."

"Nelson had a translight drive, did he? Well, that explains Trafalgar."

"No, ma'am, but he always puked his ring when he went to sea...."

Osman smiled despite herself. She was grateful not to see her breakfast in her lap. "Could be worse, then."

The view from the forward bulkhead projection was a dense, featureless void far blacker than normal space. But it wasn't just Port Stanley that had slipped into a different dimension. Osman found herself in a new reality as well. This wasn't ONI. Nobody here was calculating the best moment to make a play for her job or sending their AI to hack her systems. The people around her were just doing a job and watching their buddy's back, not looking for the best place to insert a knife in it. Osman suddenly found herself disarmed by something that wasn't exactly innocence-they were ODSTs, after all-but that pressed the same button in her.

Uncomplicated. Straightforward. Transparent. Loyal. No threat. Well, not to me, anyway.

"Okay, people, I make it forty-eight hours to Brunel, so familiarize yourselves with the ship," Osman said. "BB, what was in that databurst?"

The AI flashed an image onto the bulkhead display. It was a video transmission showing the pennant code ident of UNSC Ariadne. Osman wasn't an engineer, but she could recognize an accelerator-shielding bulkhead when she saw one. Ariadne's engineers were sending back images of a technical problem and asking for advice from Earth. There was no way of finding out what had happened until Port Stanley was back in normal space and comms were restored.

"Where is she?" Osman asked.

"She had to drop out of slip near Venezia," BB said. "The CO made contact with the colony to ask to land nonessential personnel because of the safety risks, but they refused."

"Since when did a human colony get to say no to a UNSC request for assistance? Even Venezia?" Osman realized Ariadne was only a small patrol ship, but she was still armed. Osman would have landed shuttles and argued the toss later, cannoned up if need be. Venezia had gone quiet during the Covenant War, but everyone remembered what it had done during the colonial insurrection. "Who the hell's driving that tub?"

"Commander Pasquale."

The name didn't ring a bell. She started to check her datapad for the UNSCN list, but decided to leave it for later. "As soon as we're out of slip, check whether anyone else has responded or if they're still in trouble."

"You're not planning to divert, are you?"

"I know my orders, BB. I just want to know what Venezia's playing at."