Ban Xia carefully unscrewed the bolts with a flashlight and removed the radio’s casing.

A small silver key was stuck to the inner wall of the radio casing, accompanied by a yellowed note with a drunk’s crooked handwriting: “Your New Year’s gift.”

This was truly a precious gift.

She held the key in her palm to examine it. It wasn’t much bigger than her thumb, but it had substantial weight—heavy, with a smooth silver metallic shell, like a USB drive. One end had a port covered by a translucent white plastic cap. She removed the cap and sniffed near the key’s port.

No smell.

It was hard to imagine this thing had been on the radio all along, in her room, within arm’s reach, staying with her for so many years.

During countless days and nights, the girl had eaten and slept alongside it. They were old friends who had kept each other company for many years, yet she was only just meeting it.

“Let me introduce myself.” Ban Xia held it up, closing one eye playfully. “Mr. Key, you’ve lived at my place for so many years—I won’t charge you rent!”

Hiding the key in the Icom amateur radio was the only method that could fully satisfy all requirements. Old Bai had recognized this point. If any microelectronic device could still work normally after twenty years, it would undoubtedly be the radio in Bai Yang’s bedroom. This meant the radio’s internal environment had remained stable throughout those long twenty years—as long as the radio’s motherboard wasn’t damaged, the key wouldn’t be damaged either.

Old Bai had succeeded, even though he was now vomiting and having diarrhea in the hospital, not remembering what he’d done.

The final puzzle piece of this nuclear strike operation spanning twenty years was finally in place.

That night, neither the drunk Bai Zhen nor the delighted Ban Xia had time to consider this question:

If Bai Zhen had told Ban Xia to open the radio before he hid the key, she certainly wouldn’t have found the key—the rattling sound might have been loose screws.

But after he hid the key and then told her the location, the rattling became the key.

Just a difference in the sequence of actions could lead to two completely different outcomes. If parallel universes existed, one Ban Xia would open the slow delivery and see the key, while another Ban Xia would open it and find screws in the same location.

What did this mean?

It meant that information transmission had changed reality. In the black box unobserved by Ban Xia, the source of that sound might have existed in a superposition of keys and parts, and different information transmitted from twenty years ago made this rattling ghost in the radio make different choices, collapsing into different realities.

In the process of communicating with the future, information was shaping reality.

36 hours before the projected nuclear weapon unlock.

Sunlight crept through the gaps in the living room’s floor-to-ceiling curtains, forming thin strips that quietly crawled onto Ban Xia’s dirty jeans. She sat cross-legged in the living room, munching on snacks. She had learned to make candy by heating honey mixed with pine resin—these snack-making methods were taught by the command center. The command center’s “dads” had assembled a team of survival experts specifically to teach the girl how to survive in harsh natural environments.

But they had recruited retired reconnaissance soldiers, people who excelled at wilderness survival, mastering skills like making fishhooks from zipper pulls and tin cans, turning old phone speakers into compasses, and starting fires with wood friction… Ban Xia’s survival environment wasn’t that harsh—she was surviving in an urban wasteland with readily available lighters.

Ban Xia chewed candy while tearing open a broken plastic bag and rolling it into a rope.

She was busy relocating supplies, securely packaging food and water, tying them to her bicycle, and moving east. According to the expert team’s guidance, she should prepare enough food and fresh water for three days to a week, stay as far from ground zero as possible after the nuclear explosion, and avoid approaching within five kilometers of ground zero for 72 hours after detonation. The straight-line distance from Xinjiekou to Plum Blossom Estate was exactly five kilometers.

In other words, after the nuclear explosion, she needed to hole up somewhere for a week before she could return home.

There were several choices for this temporary shelter: Nanjing Agricultural University, Nanjing University of Science and Technology, or Jiangsu Academy of Agricultural Sciences. Universities would make good bases—before the end of the world, university campuses were relatively rich and completely small societies. Ban Xia could find a classroom or student dormitory to stay in. Someone had also recommended Southeast University—an expert team member was an alumnus with an unrealistic deep affection for their alma mater, but the command center ruthlessly rejected this proposal.

“We’re still studying the residual radiation doses in the urban area after the nuclear explosion,” Bai Yang told the girl, “to ensure it won’t significantly impact your health, OVER.”

“What kind of impact?”

“Radiation sickness, and cancer, OVER.”

“Cancer?”

“Yes, long-term exposure to ionizing radiation can trigger cancerous changes in body tissues, that is, malignant tumors. You can understand it as growing a lump in your body that can’t be cured—it’s almost always terminal, OVER.”

“Long-term? How long is long-term?”

“Two to three years, or three to four years.”

“That’s still so far away!” Ban Xia felt relieved. “Three years is such a long time—why should I worry about something that’ll happen three years later?”

She thought three years was too distant, beyond what she could see even standing on tiptoe. Who would worry about what would happen in such a distant future?

This wasn’t a world where time could be counted in years. She could only think about what to do three days later, thirty days later, at most three hundred days—no further than that.

The girl carried everything downstairs breathlessly, piling it in the stairwell, then stood there with hands on hips taking inventory: salted fish, smoked meat, wild vegetables, and several large water bottles, all tightly zip-tied to both sides of the bicycle’s rear seat. Thinking about it, did she need to eat this much food in seven days? She wasn’t a pig.

But Bai Yang told her to bring more. He said food would be contaminated by radiation, and contaminated items couldn’t be eaten—eating them might cause internal radiation exposure.

Compared to Bai Yang’s nuclear paranoia, Ban Xia was much more relaxed. Once she heard that the nuclear explosion’s effects on her would take years to manifest, the girl became fearless, even feeling like humming a tune. Among all the terrifying things in the world that could take your life in an instant, nuclear bombs were quite gentle.

No wonder they called her Miss Qiu.

Ban Xia pulled the key from her pocket—it was ice-cold. For some reason, this thing never seemed to warm up no matter how long she carried it.

The countdown to nuclear weapon unlocks entered its final 24 hours.