The city still looked imposing, despite being lost and deserted for so long. Professor Tomás was amazed to have found it.

—If it wasn't for your persistence, Professor, I would have given up the search.
—I know Danny, you still don't have those needs that only time reinforces, but we can't get carried away by banalities, it's better to look for what this city hides.
They continued walking to enter those streets that nature had almost erased.
—What are we looking for, professor?
—A cell regeneration machine, it's hidden here, there was a battle for it and the city was contaminated, that's why it was abandoned.
—But professor! Aren't we in danger?
—Take it easy, those effects are gone now.
—And how do you know that?

—You've never asked so many questions before, —said the professor, —Well, my great-grandfather was a scientist and he created the machine with a group of technologists, molecular engineers and other men of science. For this project a lot of sick people were sent to this city, many of them already without a chance to live, and with this machine they returned to the world of the healthy.

—That sounds like a fiction story, nobody mentioned any of this at the university; remember that my studies are in microbiology and quantum mechanics.
The professor smiled and fell silent.

—We'd better look..., wait, I have to look at some data I have with me.
The professor grabbed his bag and searched carefully, Danny looked at it with curiosity, the professor took out a small notebook and looked for the data he needed.

—That remote day the tests were done with the first patients and the results were positive, everyone was left with their mouths open. Black Juan, Luna Dugarte and others that I don't remember were born again. The chief technologist, when he realised the results, made a plan to get hold of the machine, he hired a group of pirates, they invaded the city and created chaos, all the citizens had to fight, but the invaders were better armed. The scientists had to use a gas bomb that was being researched and when it burned it burned and contaminated everything, nobody was saved and the city was left without inhabitants.
—Was your great-grandfather in that fight?
—Yes, thanks to him I can tell you this, I have read his notes many times, he had time to hide everything.
—And how did you know about it?
—I'm not going to tell you that, there are some things it's better not to know.
Danny made a gesture that the professor couldn't see.

Professor Tomas knew that there were more interested in that secret and that the explorers who came were looking for something more than environmental sanitation studies, he remembers very well the man who came asking about my great-grandfather, he pretended to be a member of the army, I don't know how he knew my filial status, but he asked so many questions, I only gave vague answers. That alerted him and from that moment on everything I did was kept in two records.

—Do you have any idea where to look professor?
—There is an entrance that is located at the bottom of one of the buildings, but nature has hidden it even more.
—Professor, you speak as if you had been here.
I didn't have that chance, but I've been deciphering my great-grandfather's notes and the data my father got for a long time.
—How did they get into your hands?
—I told you, some things must be kept secret... Look over there, the monolith!
The professor pointed to a mound covered with moss and grass. Danny approached it and examined it carefully.
—But this is a stone, Professor Tomas!
—The moss must be removed.

With the great-grandfather worked a very select group of men and women, each thing that was achieved was kept by different hands, he knew that those experiments were monitored, What he did not know, was who was doing it, so they were prepared to protect and defend their research. What he was doing could fall into the wrong hands.

—Who built this city, Professor?
—All the people involved in the project. The only thing I can tell you for sure is that it wasn't the Atlanteans, — the professor smiled, but Danny seemed to resent the answer.
—Professor, there seems to be a ladder here!
The professor walked over to the site, then turned around as if looking for a landmark.
—Let's get the moss off.
Danny moved quickly, showing a bit of anxiety, the professor was looking at him, he sensed he was keeping secrets, on this trip he had time to observe him, he didn't want to jump to conclusions, yet, he needed to.
—Come on, professor! There are some moving stones.
—It looks like it, let me examine it, yes, it's just a bit dirty, it needs to be scraped well.
Danny took out the knife and began to clean it.
—Ready, professor!
The professor already had a rock in his hand, which he had taken out of his bag, which he put into the hole and pressed hard, there was a crack, he didn't want to show the emotion he was feeling and kept calm.
—Let's try to turn the rock.
—What's wrong?
—It's just stuck, we'll clean the bottom, and try again.
This time the monolith turned and at the bottom of the stairs the floor began to open up. The professor looked at Danny's face, it was as if he was waiting for that moment. He remembered the chief technologist, it was his same laugh.

—This is unbelievable Professor, everything is intact! Just a bit of dust and mould... where is the machine?
—Don't hurry, we've been looking for so long without knowing if we would find it, now we have it.
—That's right, professor, but I can't wait to see it.
—And so am I.

The warhead shot up to a considerable height and exploded, the smoke invaded every corner of the city and everything went to sleep, in the laboratory everything was slower. Despite being prepared for that possible moment; panic was painted on every face. I told Dr. Raydis to run to the adjoining basement, put on a mask to seal off everything and activate the protection systems so that no one could find the machine. The doctor was waiting for me in anguish, she could hardly breathe, I grabbed her and we entered the capsule.

—There's the machine! It's the one covered with a special fabric.
—You know a lot about this, professor, do you see what I have in my hand? It's a locator and they're coming, soon you'll hear the helicopters.

Of course! Your face seemed familiar to me, you must be related to Engineer Di Pietro, I've seen that face many times, the chief technologist, the one who worked with my great-grandfather.
—And who are you, professor?
— I already told you, the one who invented this machine was my great-grandfather, I'm his descendant.
—But you know so many details, it's very strange.
—Do you want to see the machine? -Me too! Even if it's the last time, you just have to remove the presses that hold the fabric.
Danny hurried to remove the presses and the miracle machine appeared.
—It's a simple machine, but it works miracles.
At that moment the sound of helicopters flying over the city could be heard.

—They are here Professor Tomas, I think you know, what your grave will be, all my family will thank you for paying your great grandfather for killing my uncle Di Pietro, we will become rich.

While Danny was messing with the machine, the professor lowered a lever and some chains fell on Danny leaving him stunned, the professor ran and stepped on the locator, then he went to a board, opened it and activated some buttons.

—I'm sorry boy, I thought you smarter.
—You're going to pay for this, Professor Tomas.
—Your friends will now have to go down and search, I'm sorry for you boy, this machine you are looking at, is the first prototype, the other one is over there, behind that wall, bye bye boy!

The professor went into the other room and Danny started to get out of the chains, he put his hands in his pocket and pulled out a gun. When he entered the professor was inside a capsule that was pulsating with very bright lights. Danny fired several shots, but was blinded by a glare.
—Where are you, Professor? I'll find you!

Professor Tomas recalled the events of that day.
—Dr. Raydis, is everything ready?
—Do you think we'll get out of this?
—Yes! We can save ourselves, now more than ever," he pressed the button and the time machine transported them.

At that moment the helicopters came down because they lost the signal, when the men start to walk, a big explosion shakes the mountain and the city ends up disappearing.

_{Translated with www.DeepL.com/Translator (free version)}