He thought briefly about disengaging and alerting security, but rejected the idea because it would break his contact with the intruder. The Raku security deckers would probably find the outsider in short order, but in the meantime no one would know what he had been doing. And when they caught up with the icon, a dogfight would likely dump the intruder out of the Matrix, It would get rid of the intrusion but not the mystery behind it. Sam wanted to know who was impersonating his friend.

The icons slid down the datalines, passing by some nodes and through others. Occasionally, they passed images of red neon samurai. These guard figures were fixtures of the Renraku Matrix, the software that provided intrusion countermeasures, or what decker slang knew as ice. The guards were Matrix versions of Renraku’s elite Red Samurai security forces, though the icons looked more like ancient Japanese warriors than the real guards in their neo-feudal body armor. As Sam expected, none of the samurai moved to oppose them. The passcodes embedded in their icons attested to their legitimate presence. Whoever was manipulating the Jiro icon was counting on such protective coloration.

In some of the areas through which they moved, the Matrix imagery was muddied, the sharpness of line in the constructs less than standard. At the first few nodes where the phenomena was obvious, the Jiro icon paused, seemingly interested in the effect. This was another clue that the intruder was an outsider, for every Renraku decker was familiar with the fuzzy areas that had become increasingly common along the datalines of the Raku architecture. The imagery-haze phenomena were random in duration and location, seeming not to affect computer performance. None of the deckers knew the origin of the disturbances, and their reports had drawn nothing more than a directive to continue logging all encounters with the phenomena.

The intruder spent time in several datafiles, but not once did Sam observe the stillness and flicker that he associated with downloading a file into a persona’s memory. If the Jiro icon’s controller was not going to steal any significant data, what was he up to? Was he simply a “joyrider,” using Jiro’s terminal to play around in the Matrix?

The intruder moved on.

At last the Jiro icon stood before the glittering barrier that the company deckers had tagged the Wall. The Wall was a featureless expanse of sputtering static, shades of gray contrasting starkly with the soft blue glow that suffused the Renraku architecture. This was forbidden territory, even to Raku deckers. The Jiro icon remained a long moment before the barrier as though contemplating it.

Was this the intruder’s goal? An assault on the Wall? Sam disengaged the Tag Along just as the Jiro icon stepped forward, merging with the Wall and vanishing from his perception. Before Sam could enter the alert code, the icon reappeared, tumbling backward through the Wall. The clown-shape flickered, hissing and sputtering as the icon crashed into and skidded along the invisible surface that was the “floor” of the Matrix.

At the same moment, the Wall extruded a samurai that was of a piece with its parent, a menacing shape of static. The shifting surface tones blurred and disguised the detail in the samurai icon’s imagery. It stepped free of the Wall, drawing a katana from its sash as it advanced on the Jiro icon. The sword blade crackled with lightnings as the samurai swept it up.

The Jiro icon rolled away from the first blow, leaving behind a ghostly image of itself. The samurai icon advanced on the ghost image. As the ghost struggled to rise, the samurai attacked, its katana slicing through the ghost’s neck, neatly decapitating it. The head had barely separated from the ghost’s body before both winked out of existence.

Snapping its head to the side, the samurai icon focused on the real Jiro icon. Though the deception had bought only a fraction of a second for the intruder, it was enough for him to ready an offensive program. The interior icon held a deadly looking pistol while the Kabuki overlay superimposed a sputtering matchlock handgun on the standard Renraku Matrix image of the attack program. Chrome salaryman and wireframe clown raised their weapons, firing as the samurai charged.

The pistol roared on autofire. The reflection matchlock, operating as its prototype never could, fired again and again. In a crazy kind of slow motion, Sam saw the bullets impact the sputtering static armor of the samurai. There was no perceptible damage.

Reaching its opponent, the samurai icon loomed over the intruder. The katana swept up above the armored head and poised briefly before flashing down. The sword sliced through the outline clown but failed to connect with the inner chrome shape as the Jiro icon threw itself to the side. The wireframe outer Image vanished with a pop. The samurai took another step forward, twisting its body around to convert the momentum of its swing into another strike. The blow caught the Jiro icon as it tried to stand, staggering it backward. The chrome surface of the Jiro icon blackened where the sword had touched.

As the karana swept up, the battered remnant of the Jiro icon lifted an arm in a futile gesture of defense. The sword whooshed down, slicing through the upraised arm and driving into the chromed breast of the icon.

The Jiro icon vanished instantly. The samurai remained poised in full extension from the deadly blow, then snapped to an en garde pose. Above its head, the sparkling blade hissed evilly.

Sam remained still as the gray and black samurai turned in his direction. What he had just witnessed was not a computer-moderated game, nor a training exercise, nor a trideo entertainment. Its imagery may have been virtual, but its effects had been very real. The intruder controlling the Jiro icon was now likely dead or a mindless husk, the higher functions of his brain destroyed by the deadly attack of the computer-controlled samurai. Sam feared the samurai’s scrutiny as the dark eyeholes of the armored facemask swept across his position, but the guard icon merely sheathed its sword. With a contemptuous swagger, the samurai turned back to the Wall and stepped into the flickering static. The figure merged with the Wall, vanishing as though it had never been.

Alone on the plain outside the Wall, Sam considered his options. If he reported the incident to his superiors, he would have to confess to following the Jiro icon instead of reporting it immediately. It would also mean revealing that he had observed Renraku’s ownership and use of illegal black ice.

Sam’s head ached and his fingers were cold as they hung poised over the keyboard. He stared at the Wall, half-seeing images of destruction in the volatile surface. He could do nothing here. Instead of retracing his path to the datastore he had been researching, he jacked out.

His icon disappeared from the Matrix as his awareness returned to the cubicle where his body sat hunched over his cyberterminal. With a sigh, he pulled the plug from the datajack on his left temple. He rubbed his face with both hands, trying to banish the nagging headache that always accompanied his forays into the Matrix. Usually the rubbing replaced the dull pain with a clean tiredness, but today his head continued to throb.