Yet any material has a breaking point. In the case of the Marines' uniform armor, that point was high but not infinite. The first bead shattered on the surface, the metal and glass bits flicking out in a fan to pepper the underside of the Marine's chin even as his hand reached once more for his own sidearm. The weight was coming off his feet as he started to drop to a kneeling position when the second bead hit a few centimeters above the first. This bead also shattered, but the extra energy began to splinter the molecular bonds of the resistant material.

The third bead did the trick. Coming in on the heels of the second and slightly lower, it shattered the kinetic armor like glass, finally throwing some of its mass into the now unprotected Marine's sternum.

Ensign Guha wiped the blood off of the keypad and attached a device to the surface temperature scanner. She shouldn't have had the codes to enter Engineering, or the facial features, for that matter. But any system is subject to compromise, and this one was no exception. The security systems saw the IR features of the DeGlopper's chief engineer and received the correct codes timed in just the way the chief would have tapped them. She stepped through the open blast-doors and looked around, pleased but not surprised that there was no one in sight.

The engineering spaces of the ship were huge, taking up well over one-third of the interior volume. The tunnel drive coils and the capacitors to feed them took up the majority of the space, and their keening song filled the vast compartment as they sucked in energy voraciously and distorted any concept of Einsteinian reality. The light-speed limit could be violated, but it required immense power, and the tunnel drive gobbled up internal volume almost as greedily as it did energy.

But the field of the tunnel drive system was more or less fixed and independent of mass. Like the phase drive, there was a specific limit to the maximum volume of the field which could be generated, but the mass within that field was unimportant. Thus the huge ship carriers of the various Imperial and republican navies that battled among the stars. And thus the vast size of the interstellar fleet transports.

But all of it depended on power. Enormous, barely controlled power.

Ensign Guha turned to the left and followed the curving passage as the tunnel drive thumped out its keening star song.

Kosutic nodded at the guard on the magazine deck as she stepped back out the hatch. The guard, a newbie from First Platoon, had stopped her at the hatch and insisted that she pass the facial temperature scan and key in her code. Which was exactly what she was supposed to do, which was the reason for the sergeant major's nod of approval. However, Kosutic also made a mental note to talk to Margaretta Lai, the trooper's platoon sergeant. The trooper had clearly loosened up when she recognized the sergeant major, and she needed to learn to doubt everything and everyone. Eternal paranoia was the entire purpose of the Regiment. There was no other way to guard effectively in this day and age.

Despite early gains in processing, it had taken humanity nearly a millennium after the invention of the first crude computers to develop a system of implanted processors that interfaced completely with human neural systems without adverse side effects. The "toots" were still cutting edge and being constantly refined... and they were a security planner's nightmare, because they could be programmed to take over a person's body. When that happened, the unfortunate victim had no control over his own actions. The Marines called people like that "toombies."

Some societies used specially modified toots to control the actions of convicted criminals, but in most societies, including the Empire of Man, such a use of the hardware was illegal for all but military purposes. The Marines themselves used the system to the fullest as a combat aid and multiplier, but even they were wary of it.

The big problem was hacking. A person whose toot had been "hacked" could be forced to do literally anything. Just two years ago, someone had mounted an assassination attempt on the prime minister of the Alphane Empire by using a human official with a hacked toot. The hacker had never been found, but once the security protocols were solved, it had been a ludicrously simple thing to do. The toots were designed for radio-packet external data input, and a small device disguised as an antique pocket watch had been found in the official's possession. It was speculated that it had been given to him as a gift, but wherever it had come from, it had taken his toot over. It was as if the official had been possessed by a demon hidden in the ancient Pandora's box.

Since then, all members of the Regiment and all close servitors of the Imperial Family had been required to go through random scans, and the security protocols of their toots had been updated yet again. Kosutic knew that, but she also knew there was no such thing as a perfect defense.

She made a note to hunt down Gunny Lai on her toot and smiled at the ambiguity of her own actions. She'd started off in the Marines before the day of the devices; but she'd become as dependent on them as everyone else. It was a humorous irony, in a bitter sort of way, that she now saw them as the single biggest threat to her charges.

She stepped onto the elevator and checked the duty roster again. Hegazi was on Engineering. Good troop, but new. Too new. Hell, they were all too new; eighteen months was just enough time to get very good at their jobs, then most went on to Steel. The few who stayed were rarely the best. She thought of Julian and laughed. Of course, there was best and best. But she intended to remind Hegazi, who was a good troop overall, that he needed to be totally one hundred percent paranoid at all times.

She stood in the pool of the Marine's blood. She hadn't bothered to check his pulse; nobody who'd lost that much blood was alive, and she was too busy considering what to do to waste time on pointless gestures. She didn't consider for long—the Marines didn't exactly pick ditherers as the senior noncoms of The Empress' Own—but there was always enough time to screw up, so there had to be enough to make the right move, as well.

She tapped her communicator.

"Sergeant of the Guard. Full load out to Engineering. We have a breach. Do not sound General Quarters."

She cut the communication. The guards would contact Pahner, and the assassin wouldn't be alerted, for the Marine communicators were encrypted. Of course, the saboteur—and sabotage had to be what the killer contemplated—could have left any of half a dozen telltales along his backtrail to warn him that he'd been discovered.

Kosutic plucked the sensor wand off the dead guard's belt and swept the hatch. No obvious traces there. She keyed in the entry code and went through the hatch fast and low as it opened. The blood was already coagulating, and the body was cooling, so the assassin probably wasn't on the far side of the hatch. But Eva Kosutic hadn't survived to be a sergeant major by depending on "probably."

"Engineering, this is Sergeant Major Kosutic," she said into her communicator. "Do not, I say again, do not sound an alert. We have a probable saboteur in Engineering; your guard is dead." She swept the sensor wand around. There were heat traces everywhere, but most went straight ahead. All except one. A single trace split off from the pack, heading to the sergeant major's left, and it looked fresher.

"What?" the communicator demanded incredulously. "Where?"

"It looks like somewhere in quadrant four," she snapped. "Get on your scanners and vids. Find them."

There was a moment of silence from whoever was on the other end of the line. Then—