Cheng Xin awakened to find herself in weightlessness.

Hibernation wasn't like regular sleep. A hibernator didn't feel the passage of time. Throughout the entire process, one could only feel time during the hour spent entering hibernation and the hour emerging from it. No matter how much time passed during hibernation, subjectively, the hibernator only felt that he or she had slept no more than two hours. Thus, waking up always involved a sharp break, a feeling that the self had passed through a door in time and emerged into a new world.

Cheng Xin found herself in a white spherical space. She saw that 艾 AA was floating nearby, dressed in the same skintight hibernation suit. Her hair was wet and her limbs were spread out powerlessly; clearly, she had just been awakened as well. As their eyes met, Cheng Xin wanted to speak, but the numbness caused by the cold had still not left her, and she couldn't make any noise. AA shook her head, meaning that she was in the same state and didn't know anything.

Cheng Xin noticed that the space was filled with a golden light like the setting sun. The light came in through a circular window -- a porthole. Outside the porthole, Cheng Xin could see only blurred streaks and swirling lines. The lines were arranged into parallel bands of blue and yellow, revealing a world covered by raging storms and torrents, clearly the surface of Jupiter. Cheng Xin saw that the surface of Jupiter looked much brighter than she remembered.

She discovered another amazing fact as well: The place they were in stayed at rest relative to the combined space city, but Jupiter was slowly moving in the background. Based on the brightness of Jupiter, they were now on the side facing the Sun, and she could see the shadow of the combined space city against the gaseous surface of Jupiter. After a while, the Jovian terminator appeared, dividing Jupiter's day from night, and she saw the monstrous eye that was the Great Red Spot drifting into view. Everything confirmed the fact that both the place they were in and the combined space city were not in Jupiter's shadow and did not orbit the Sun in parallel with Jupiter; instead, they were Jupiter's satellites and revolved around the gas giant.

Strangely, the wide, raging cloud band in the middle reminded her of the Yellow River. She knew, of course, that an eddy in this "Yellow River" was big enough to contain the Earth. Against this background, Cheng Xin saw an object. The main body of the object was a long column whose sections were of different diameters. Three short cylinders were perpendicularly attached to the main column at different locations. The entire assembly slowly rotated around the axis of the column. Cheng Xin decided that she was looking at a combined space city formed from eight separate space cities docked together.

AA shook her head again. "No idea. I think we're on a spaceship."

"Where are we?" Cheng Xin asked. She was finally able to speak in a hoarse voice, but she still couldn't move her body.

They continued to drift in the golden glow of Jupiter, like a dreamscape.

The voice came from an information window that had just popped up next to them. In the window was an old man with a head full of white hair. Cheng Xin recognized him as Cao Bin. Based on his age, she realized that she had leapt across another long stretch of years. Cao Bin told her that it was now May 19 of Year 67 of the Bunker Era. She realized that fifty-six more years had passed since her last brief awakening.

She avoided life by staying outside of time, and she watched as others aged, seemingly in an instant. Her heart was filled with regret and guilt. She decided that no matter what happened from now on, this was her last hibernation.

"You're on Halo."

Cao Bin told them that they were on the latest ship to bear the Halo name. It had been constructed only three years ago. After the Halo City Incident, more than half a century earlier, he and Bi Yunfeng had both been convicted, though both had served short sentences and then been released. Bi Yunfeng had died more than ten years earlier, and Cao Bin brought along his well wishes for her and AA. Cheng Xin's eyes moistened.

"Life in the cities is once again like being in paradise. It's too bad that you won't get to see it, because there's no time." Cao Bin paused. Cheng Xin and AA exchanged uneasy glances. They realized that he had been so loquacious until now because he was trying to delay this moment.

Cao Bin also told them that there were now fifty-two large space cities in the Jupiter cluster, most of which had been combined into bigger cities. What they could see was Jupiter Combination II. Since the advance warning system had been refined twenty years ago, all cities had decided to become Jovian satellites. Only after an alert was issued would the cities change orbit and go into hiding.

Cheng Xin's heart tensed. It wasn't because the attack had arrived -- humanity had been preparing for this moment for more than a century. Rather, she sensed that something was wrong. She and AA had been awakened by contract. It would have taken at least four to five hours for them to recover to this stage, which meant that the alert had been issued some time ago. But outside the porthole, Jupiter Combination II had not disassembled nor changed its orbit, but continued to drift as a Jovian satellite, as though nothing had happened. They turned to Cao Bin: The centenarian's expression was too placid, as though hiding utter despair.

"Was there an attack alert?"

Cao Bin nodded. "Yes, there's been an alert. During the last half century, there were two false alarms, and each time, we almost awakened you. But this time it's real. Children -- I'm already one hundred and twelve years of age, so I think I can call you that -- the dark forest strike is finally here."

"I'm at the advance warning center," Cao Bin said, and pointed behind him.

"Where are you now?" AA asked.

Cheng Xin saw a hall behind him that looked like a control center. Information windows filled almost every bit of space. The windows drifted around the hall, but new windows kept on popping open before them, only to be covered in turn by still newer windows -- like the flood after a burst dam. But the people in the hall seemed to be doing nothing. Half of them were in military uniforms, but they all either stood leaning against a desk or sat still. Everyone had dull eyes, and all had the same ominous calm expression that was on Cao Bin's face.

It shouldn't be like this.

This didn't look like a world hunkered down inside a bunker, certain it could survive the attack. It looked more like three centuries ago -- no, four centuries ago now -- when the Trisolar Crisis had first developed. Back then, at the offices of the PIA and the PDC, Cheng Xin had seen this kind of atmosphere and expression everywhere: despair against some superpowerful force in the universe, a kind of numbness and indifference that said We give up.

Most of the people in the control center were quiet, but a few whispered to each other with somber faces. Cheng Xin saw a man sitting numbly. A cup had fallen over on the table in front of him, and a blue liquid spilled off the table onto his pants, but he ignored it. On the other side, in front of a large information window that seemed to show some complicated, evolving situation, a man in military uniform embraced a woman dressed as a civilian. The woman's face seemed wet…

"There's no photoid."

"There's no point. The bunker is useless," Cao Bin said, lowering his eyes.

"Why aren't we entering Jupiter's shadow?" AA pointed at the combined city outside the porthole.

"How far is the photoid from the Sun?" Cheng Xin asked.

Cao Bin gave a wretched laugh. "A slip of paper."

"Then what have you found?"