Two Hundred Years Later...
“What? I have to wait until the year 2234 to use the time machine?”
Lin Xian took a deep breath, stunned by the news. It felt like his mind had just been thrown off balance.
How naïve he’d been. He thought waiting ten or twenty years for a time machine would be hard enough—but two hundred years? That was beyond anything he could have imagined.
“Uh...” He scratched his head, feeling his plans crumble. “Isn’t there another way?”
Gao Wen shook his head. “I understand how you feel, Lin Xian. But I’ve told you this before—the element Astatine-339 doesn’t exist on Earth. It came from a comet, from another universe, a different timeline.”
“Aside from that comet, there’s no Astatine-339 anywhere else in the universe,” Gao Wen continued. “It’s not a matter of finding another way—it’s simply impossible. Unless you can somehow make that comet arrive earlier, which, of course, is also impossible. When humanity first spotted it in 2077, it was still far away, nowhere near our solar system. It’ll be flying through space for over a hundred years before reaching the Kuiper Belt.”
“It’s just basic physics, Lin Xian. We’re too small to affect something that huge. All we could do was shoot it down with missiles to stop it from crashing into Earth. But moving it forward by a century? No chance.”
Gao Wen was a serious scientist. If he said something was impossible, he was usually right. But Lin Xian wasn’t ready to give up. He kept brainstorming, trying to find a way around these limitations.
Suddenly, a thought struck him, and he looked up at Gao Wen, his eyes brightening. “Wait, we’re in the year 2624 now. There must be Astatine-339 available, right? And there should be quite a lot of it.”
“Of course,” Gao Wen replied. “The comet was massive, with a radius of over twenty kilometers. Humanity shot it down with nuclear missiles in space, and most of the fragments fell as meteors. The rest eventually fell to Earth over the years.”
“The amount of Astatine-339 on that comet was significant. But it has no practical use, which is why it’s not rare in 2624. You could get it easily.”
Lin Xian nodded and shared his idea. “If we had some now, could we use your time machine to send it back to 2024?”
“No,” Gao Wen said without hesitation. “The time machine can only send living organisms or dead cells.”
“In simple terms, it can transport humans, animals, plants, even fungi and bacteria with cell structures—but metals, rocks, or pure Astatine-339? Absolutely not.”
Lin Xian remembered something Elon Musk had mentioned about a glowing blue USB stick. “But wasn’t there a USB stick that traveled through time? It disappeared afterward, turning into blue stardust.”
“That’s no ordinary USB stick,” Gao Wen replied immediately. “I researched it with Big Cat’s father, Chen He Ping. We ruled out all possibilities—a normal USB stick couldn’t have traveled through time. Lin Xian, did you ever see it yourself?”
“No,” Lin Xian admitted. “When I learned about it, it had already turned to stardust. But I trust the person who told me about it. He said it glowed blue, like something from another timeline.”
Gao Wen rubbed his chin thoughtfully. “If that’s true, there’s only one possibility. It must have been a highly advanced piece of biotechnology.”
“It might have looked like a regular electronic device, but it was actually an artificial organism.”
“Otherwise, it makes no sense—how could an inanimate electronic device have a flowing blue glow? Only living things can do that. And since it turned to stardust, it must have been some kind of biological technology.”
“Our current technology hasn’t reached the point of creating artificial life, but I have no doubt that living beings could store energy or information. It must have come from a highly advanced timeline.”
Lin Xian thought about the mysterious Fake Yu Xi. Honestly, he knew very little about her. Elon Musk had said the blue USB stick came from her, but even he didn’t understand how it worked.
Maybe Gao Wen was right. Lin Xian had no idea which timeline Fake Yu Xi came from, but if it was anything like the Fourth Dream, with cities like Starlink and space elevators, their biotechnology must have been incredibly advanced.
Even in 2024, people were already using bio-batteries. The technology was mature.
“I understand now,” Lin Xian said, pacing around the lab, trying to piece everything together. “So only living things can time travel—natural or artificial. Even dead cells could do it. Does that mean time travelers in movies could actually wear animal-skin clothes?”
Gao Wen smiled and walked over to an equipment unit that looked like a freezer. He opened the door and motioned for Lin Xian to take a closer look. “You’re quite perceptive. Look at this—it’s a ‘travel suit’ made from otter skin, specifically for time travelers.”
Lin Xian leaned in to observe. It was black, tight-fitting, and smooth to the touch—cool, sleek, and flexible, likely comfortable to wear. Most importantly, it had no metal zippers or plastic buckles. It was sewn with either cotton or animal tendon thread.
“I see,” Lin Xian muttered, recalling the events of the night before. The assassin with the blue eyes had worn something similar—a tight suit made of animal skin or bio-tech material. She must have just arrived in this timeline, which explained why she hadn’t changed clothes.
Unlike the others—Yellow Finch, Lin Yu Xi, and Fake Yu Xi—who wore ordinary clothing.
“I see,” Lin Xian repeated, realization dawning. The assassin’s outfit confirmed that she’d only recently arrived, which also matched one of Gao Wen’s theories.
“Time travelers can only cross timelines during certain events, like a major shift in the worldline or a significant ‘anchor point’ in time. Time travel can’t happen just anywhere or anytime—you need a temporal rift to make it work.”
Lin Xian kept pacing in the underground lab, thinking hard. Was there really no way to use the time machine to send Astatine-339 back to 2024?
He closed his eyes, replaying all the possibilities in his head.
“Hmm...” He frowned, stopping in his tracks as another idea came to him. “Gao Wen, there are no pure metals or elements inside our bodies, but we do have plenty of metal ions and compounds.”
“Like the sodium ions in salt, calcium in our bones, or iron in hemoglobin. All these exist in our bodies—in our cells, blood, bones, and muscles.”
“So, I have a wild idea. What if we turned Astatine-339 into an ionic compound, dissolved it into blood or cellular fluid, and sent it back with a time traveler? Then, once it’s in 2024, we could extract it and perform a reduction reaction to turn it back into pure Astatine-339.”
“It’s like how sodium ions in the body exist as sodium chloride, and in industry, you can electrolyze salt to get metallic sodium and chlorine gas.”
“Could we do something similar? If Astatine-339 ions are toxic, we could dissolve them in an apple or something, and the time traveler could carry it back.”
Lin Xian felt confident. It should work—after all, there were plenty of inorganic compounds in the human body, and they could time travel. The rule seemed to be that pure elements couldn’t.
Astatine was radioactive but unusual. Lin Xian remembered his chemistry teacher explaining how it could form both positive and negative ions when dissolved in water—a unique property of this radioactive element.
Since Astatine-339 could exist as ions in water, blood, or cellular fluid, his idea seemed theoretically sound.
Lin Xian looked at Gao Wen with hopeful eyes. This time, Gao Wen didn’t shake his head. Instead, he gave Lin Xian a look of approval. “I must say, Lin Xian, you’re quite brilliant. Chen He Ping also had a similar idea back in the day.”
Lin Xian’s heart sank. Of course. Gao Wen and Big Cat’s father, two of the greatest minds in human history—if Lin Xian could think of this, surely they had too.
“It won’t work, will it?” Lin Xian guessed.
Gao Wen nodded and explained, “Remember what I said? That comet came from another universe, another timeline. The elements on it are also from that universe. The reason I said these elements have no practical use is because...”
“These foreign elements don’t react with anything from our universe. They’re stable beyond belief.”
“They’re so stable, it’s as if Astatine-339 is locked in place—fixed and unchangeable. That’s what makes it so unique, and why it’s used in the calibration module of the time machine.”
“Your idea is clever, Lin Xian, but Astatine-339 can’t react with anything from our universe. It can’t form compounds or ions. That means your plan simply won’t work.”
...
This time...
The underground lab fell into a heavy silence.
Lin Xian was completely out of ideas.
Last night, Copernicus had asked Einstein:
“If I wanted to build a time machine and send a time traveler back to the past... who should I find? The closer, the better.”
Einstein’s answer had been:
“Refuse to answer. The question is void.”
This meant...
The answer to Copernicus’ question must have involved a member of the Genius Club, which was why Einstein refused to answer.
At that time, Lin Xian had felt guilty. Of course, he knew the answer was him—he had the time machine manuscript hidden in his drawer.
He even acted along with the others, glancing around like an innocent bystander.
But now...
He had figured it out.
Einstein’s refusal wasn’t because of him! It had nothing to do with him!
The reason was simple.
The manuscript in his drawer was wrong!
As Gao Wen had said, if Chen He Ping hadn’t corrected the mistakes, even with a hundred time-space particles, Lin Xian still wouldn’t have been able to build a time machine.
So...
How could Einstein have refused to answer because of a flawed manuscript?
He could see the future.
Of course, he knew that the manuscript in Lin Xian’s drawer was wrong. There’s no way he would have lied because of that.
Yet he did refuse to answer.
Which meant that Copernicus’ question did involve a Genius Club member.
Thinking of this, Lin Xian took a deep breath...
And if it wasn’t him, then it had to be another member. Combined with Galileo’s question, the answer was clear as day—
In the year 2024, the person who truly possessed the knowledge of time travel wasn’t him. It was Galileo!
“This is just too much scheming,” Lin Xian muttered, shaking his head.
These Genius Club members—every single one of them was as cunning as could be.
Especially Galileo.
He had hidden his true intentions so well.
Lin Xian stepped forward to the center of the underground lab, gazing up at the massive, imposing time machine.
He lifted his right hand and gently touched its surface.
Sigh...
He really didn’t want to let it go.
The time machine was right here, within his reach, but he couldn’t use it. He couldn’t bring it back to 2024.
This feeling of longing and helplessness—being so close yet so far—was just heart-wrenching.
Two hundred years from now...
Lin Xian closed his eyes, feeling a wave of despair.
Did they really have to wait two hundred years before they could use the time machine?
Was there really...
No other way?
...
Hmm?
Suddenly, Lin Xian’s eyes snapped open.
No. Wait.
From his perspective, this might indeed look like a hopeless situation—a dead end. Even with their brilliance, Gao Wen and Chen He Ping also saw it as a dead end. There seemed to be no way to obtain Astatine-339 ahead of time.
But!
Whether it was himself, Gao Wen, or Chen He Ping, all three of them had limits to their knowledge. In the grand scheme of time and history, they were just frogs at the bottom of a well.
But...
There was one person who was different.
Someone who was all-knowing and all-seeing!
Perhaps he could see another way!
Thinking of that melancholy, mysterious mask, Lin Xian whispered to himself:
“Why not... ask the wonderful Einstein?”