The three female chiefs left, and Silvia and Annina were asleep too. The world without women was a quiet one. Xia Lei arrived at the villa on factory grounds, carrying a backpack. The villa had been under constant guard, by his own guards and the Chinese National Guard. No one else had moved in after Silvia and Annina had moved out. Under the cover of night, the lightless villa looked like a haunted house.

The two Special Forces soldiers guarding the door saluted Xia Lei. Xia Lei nodded in acknowledgement and went into the villa unhindered.

Xia Lei opened up the backpack when he got to the underground laboratory and took out what was inside. There was just a notebook, that silver-coloured alloy, and the ancient canvas which had what was on it vanished. These things were what he had taken from Bobbio, Italy, from da Vinci’s labyrinth. There were a few other things, like da Vinci’s manuscripts and oil paintings, but he had not brought those things here.

The laboratory was silent.

Xia Lei spaced out while he looked at those three things.

The ancient alloy, AE, Princess Yongmei, da Vinci, the silver-coloured alloy, the bronze book, the compass... these people and items appeared in his head, one by one. All of these were related, of course, but he could not find the thread which tied them all together.

After a long while of silent blank staring, Xia Lei picked up the notebook.

He opened it up. The first page was still the same, written in Italian.

‘If you’re reading this, it means you’ve come. I have completed the task she’s handed to me. I cannot help but imagine this very scene, and it excites me. I hope you will be able to solve the mystery of the box. I will be in Heaven awaiting your good news. She has also given me a piece of alloy. I have tried but failed at understanding its structure. Maybe you will be able to do it. The path out is before you. How did the Viking pirates enter?’

He had gone to Italy only because of Ning Jing’s painting, and what she had said while she was “possessed”. According to this message that da Vinci had left, his main motive in going into the underground labyrinth was to “awaken someone”, and the silver-coloured alloy was secondary.

‘The Knights Hospitaller called this silver metal the “metal of the gods”, and treated it like a sacred object. It must have some story behind it and be very valuable, right? I tested its strength when I was in the labyrinth too, and it is no ordinary metal. Da Vinci studied it but did not leave any research results...’ Xia Lei turned the page, and lifted the blank page after it above his head to see if the light would reveal anything on it.

The paper was very clean, and had no traces of ink at all. Under the light, he saw some faint traces — marks left by da Vinci from writing the first page.

Xia Lei remembered something just as he was about to flip the page. He put the second page under the light again and activated his zoom-in vision.

He saw something different this time. The marks left on the second page were shaped differently from the first page.

This difference meant that da Vinci had written something else after the first page. The second page would not have different markings if he hadn’t.

Xia Lei used the same method to look at the blank paper behind it and discovered more traces. These traces were barely perceptible and he would not have been able to detect them under normal circumstances without his zoom-in vision.

This discovery excited Xia Lei. He was sure that da Vinci had left something behind in this notebook.

He quickly prepared acidic and alkaline solutions of different concentrations, and carefully dabbed some on the blank paper. He did not have to use all of his prepared solutions; the first drop worked. Italian words appeared in the areas which had come into contact with the solution.

“Haha!” Xia Lei could not help laughing and dancing about in the laboratory like a child. “Da Vinci, da Vinci, you really are the smartest man on Earth. You were actually already able to make invisible ink in your era.”

Invisible ink was not a rarity in modern times and it could be bought in stationery shops. In da Vinci’s time, however, it was definitely a miraculous thing.

More of the solution was put on the paper, and the full Italian text appeared.

‘Am I the smartest person in the world? No. If I am the smartest person in this world, then I would be able to solve the mystery of the metal of the gods. To me, it is as mysterious as she is, and both are not of this world. She appeared before me 30 years ago, and she made me different from other people. Thirty years have passed, and I have gained nothing. I’m old, and not long for this world, but she is still so young and shows no hint of aging. I suspect she is an angel, and it, a part of an angel’s sword. She is an angel who has come to the human realm, and her angel sword was destroyed. She is looking for a remnant of god and must fight devils, but this is doomed to be a dangerous path full of thorns...’

Xia Lei put more of the solution on the page.

More words appeared.

‘She always brings wounds back with her, and a bit of mineral powder every time too. She would smear it on canvas every time. I asked her what the mineral powder was, and she’s never told me. I also asked her why she was painting such a strange painting and she said that if she died, a person would come here one day to awaken her. I cannot understand something like this, like I cannot understand the world of gods...’

That was the end of the second page.

Xia Lei paused, and stared blankly into space before the notebook. He was still holding the dropper with the solution, and he looked like a statue.

What da Vinci had written in invisible ink answered some of his questions but they had also shocked him.

‘She appeared before me 30 years ago, and she made me different from other people.’

This was what da Vinci had written. There wasn’t anything special about it, but it took on more meaning for Xia Lei. His abilities came from the AE capsules. If it hadn’t been for the AE capsules his father had given him, then his life would not be the way it was now. He would probably still be working at construction sites, wielding, moving bricks and living at the lowest level of society like a dog. So, the turning point of his life was due to the AE capsules.

Da Vinci was hailed as the smartest man in this world and was an all-rounder genius. His life’s turning point had been “her”. So had his life’s change been because “she” had given him AE capsules?

Hundreds of years had passed and da Vinci was long dead. There was obviously no way he could answer him now. What he did mention was a “she”, but where was “she” now?

Xia Lei turned the second page and looked at the third page.

The solution from the second page had touched the third page too, and its contents were clear.

‘She likes to sit under the scorching sun and do nothing, just look at the sun. I tried it too but I could not stand it for even a minute. She can sit like that the whole day, till the sun goes down. She said that doing this makes her stronger. I don’t understand the principle behind it. I also noticed that she never tans. Her skin is always alive with youth, white and tender. This gave me an idea and I studied the alloy from the light and heat angle. However, my efforts were still in vain...’

The third page made Xia Lei think of Princess Yongmei all of a sudden. She was afraid of the cold. She had pestered him during the treasure-seeking trip to Jerusalem and wanted a hot shower with him.

A hypothesis appeared in his head. ‘Could this “she” that da Vinci wrote about be the same person as the Princess Yongmei I met? Could the one da Vinci met be a complete one, but the one I met incomplete?’

He put more of the solution on the fourth page and new words appeared.

‘She never told me what she fights for, nor who her enemy is. She leaves the labyrinth time and time again, and comes back with injuries every single time. She never gives up, and I am unable to help her. The last time she came back was on a moonless and starless night. She was heavily injured that time and she lost her body. I cannot comprehend how she is still existing, but this is how gods are. She told me that she is dying and instructed me to do some things for her. After she left, I sealed the labyrinth and did as she instructed me, one by one. I cannot anticipate what will happen in the future. I am leaving these writings behind but with no hope that you would read them. This is just the rambling of an old man. But if you do read this, and you have awakened her, please tell her I love her.

Leonardo di ser Piero da Vinci’

The fifth page had nothing.

Da Vinci had not been able to help “her” fix her “angel sword” in his lifetime. He obviously would not have recorded his failed attempts in a notebook like this.

The hidden writing in the notebook had been found but Xia Lei could not calm down.

Now, Xia Lei could practically confirm that the “she” whom da Vinci had met was a complete Princess Yongmei. But da Vinci had not described what “she” had instructed him to do before her death. What Xia Lei really wanted to know was if any of those things she told da Vinci to do were related to AE capsules.

The alloy pieces, the box made of alloy pieces, the bronze book, the compass... These unsolved mysteries spun about in his head again, and he felt heavy with helplessness.

Da Vinci and “her” had obviously failed. He had not been able to solve these mysteries though he had spent his life working on it, and the mighty “she”, as powerful as an angel, had died in the end. Was everything he had experienced, and everything he had done, just history repeating itself? Was he sure to fail?

Ring ring ring, ring ring ring...

The silence in the basement laboratory was broken by the ringing of his mobile phone.

The ringing made Xia Lei jump, and he took out his phone automatically. He took one look at the screen and paused — there was no number calling.

Xia Lei accepted the call. “Who is it?”

“Huu... Hhh...”

Xia Lei’s heart thumped. It was her! The woman who had called him in Paris, to tell him to escape!

“Who are you?”

“This oxygen mask is getting in the way.” The voice of a girl speaking in Italian came from over the line. Her voice was clearly young, and gave him the impression that she was not yet 18.

“Who are you?” Xia Lei didn’t care about oxygen masks. He needed an answer. A concrete answer.

“All right, I’m ready. Are you ready?” said the girl.

“I... Ready for what?”

“Forget it. I’ll come to you.”

“Hello? Who are you?”

“Beep... Beep...” The busy line tone sounded.

Xia Lei kept his hold on the phone. He stood there woodenly, motionless for a long time.