We are not gods.

Deep within the earth, the secrets of life held a sacred riddle. These extreme lifeforms eat bacteria that feed on nitrogen and thrive on such particles of fatty-acid encased carbons, petrified cells of immortal proto-life. The smallest snacks it devoured metabolized raw minerals into molecules that were neither alive - nor mere chemical reactions.

We saw the chain of life, unbroken, amid the endless surfaces within limestone and basalt, within cracks of granite, where things are born and die in geologically scaled time. This realization should have made us understand that which lives - sleeping forever in the darkness - should have left it where it slept. Instead, we brought it to the surface.

To this thing, this worm, this bio-mineral-phage, our world is too easy - a feast. The caverns where it roamed like a clever demon, the microcracks and the crannies, an endless maze that adapted it to overcome any obstacle and danger. In its homeworld, deep below our delicate surface layer, magma plumes and radiation and collisions of pressure and the ever-shifting labyrinth made it into the perfect hunter, the ultimate survivor.

We are just soft and stupid chunks of abundant meat to this polymorphous horror.

In the end, our containment measures were a mere child's obstacle course for this thing.

Our first warning was when it seemed playful, reacting to us, mimicking our movements in the glass tube we kept it in.

When we first found the creature Livingstone, it was microscopic, and difficult to understand and study. It was our tampering that grew it to a sizable thing, a blob of living mass, the size of a baseball. While it waited for more nutrients it went dormant, supposedly it could hibernate like that forever. It spit out its core chromosomes and then it died, sort-of. Tendrils snaked out of its husk and pulled the living mass inside, forming a kind of walled-off super-shell. Our calculations indicated this auto-cannibalism could sustain it for perhaps a quarter-million years, even at its current size. An unnatural size for Livingstone, as it wouldn't naturally have such an abundance of nitrogen and nutrients as we had fed it, artificially.

Deep within the earth, it had to sustain itself on crumbs, but we had given it the whole cake.

The military of our country wanted us to add several more containment measures when it first showed signs of escape-artist abilities. There were a total of ten levels of containment, and we felt that seven of them were entirely unnecessary, since it had only broken out of the test tube, and never showed any more sign of strength or ingenuity. We didn't comprehend how it could adapt or learn or change shape and tactics. We didn't really conceptualize how well it understood us, while we had learned very little about it.

Livingstone might be a god, I think.

I write from this last place, as it knocks upon the door, "Shave and a haircut" over and over again, waiting for me to open the last door. I made alterations to our security, allowing me to share our findings with the rest of the world and having made an entry code that it cannot guess, as it is an infinitely long number, hundreds of digits long. There is no way it can possibly type that into the override and open the door.

Of course, we were wrong about all of its other abilities, and it made it to this final airlock, bypassing all of the unbeatable containment measures. I worry that it is merely toying with me, waiting for me to unseal the final door to the outside, before revealing it can come into this last room, where I reside. That is why I am going to stay here, with Livingstone, because this is checkmate, as long as I do not open that door, it is trapped in the lab, with me.

If it comes in before I open the door, and eats me, then humanity wins, because the last door is sealed from the inside, and only I know the password, and the biometric scans required, and the keycard which I have shredded already. Even if it can type in that numeric code outside, over a thousand digits long, an impossible guess, it will find it has eaten the last key, already broken, when it gets to me. I doubt I will be anything but a mummified corpse when it gets to me, for the oxygen will run out long before my rations, and I will die and become a dry decomposition.

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I am very afraid, I am terrified. Most of the horror has gone numb, and I am somewhat resigned to this fate. Everyone else is dead. It has killed everyone, and the nightmare has gone quiet.

Except for the sound of "Shave and a haircut" which it keeps knocking over and over again. It is both maddening and reassuring at the same time. As long as it keeps trying to communicate, I feel it has reached an impasse. It is also trying the keypad, but it cannot figure it out. It is just typing numbers into it over and over, unable to guess the impossible code I've set it to.

The first layer of containment failed when we shut off Livingstone's nitrogen ration, after waking it up for the general. It didn't like that, and it did wake up, and reached for the sealed nozzle, feeling around the edges and then it suctioned itself to the unbreakable glass and applied enough pressure somehow to crack the glass. We retreated from its chamber and watched in surprise and fascination for twenty six minutes while it continued to add cracks. Finally, it broke out, slithering gracefully out and towards the door, somehow knowing without any kind of sensory organs that we knew of, which way was out.

"It can't get through solid metal." we told the general.

It reached with a tendril and used the override keypad to type in the five-digit number and open the door.

The second containment had failed, and we were astonished, and afraid.

Livingstone withered under the flamethrowers, the specially designed toxins and the bombardment of ultraviolet light, but it did not die. Each time it broke free of its defensive shell different, smaller and more evolved, moving slower and more awkwardly, or more cautiously.

I had already retreated to the entrance, as I was too frightened to stay and watch. I had seen how it grew and fed and survived attacks and environmental hazards since it was a mere amoeba. Its actions mirrored the microscopic, and this terrified me. It was hunting, now, anticipating the evasion and defenses of the kinds of things it liked to eat. We were triggering its normal behavior over hundreds and thousands of years in the microscopic world in mere minutes and hours in our world. It made little difference to Livingstone, it just scaled up with the new scale of life it was encountering.

I'm not counting the physical attempts of security forces to fight it as a containment measure, as it was a desperate attempt to capture it or kill it as it circumvented two entire containment levels. It ignored machineguns and grenades, almost completely ineffective, but the violence taught it there was lively food nearby, and it got a taste for human flesh, eating and digesting us like vitamins, and growing quickly into something too fast and strong and large.

It had become a new predator, something it was never meant to be. I was there in the control room and it was my decision to seal off the base when all of our containment measures except the last two had failed. I made this decision out of fear and logic, combined into some kind of cold-blooded triage.

I watched and wept and shook with morbid self-loathing and the sensation of a waking nightmare as my colleagues who were trapped with it were hunted down and devoured, one by one. It took their keycards and used them to circumvent minor doors, moving up through the levels of our underground laboratories. It ate all the other samples, all the lab animals and chemicals that it found, always growing, always changing and learning.

The ninth containment was one we thought it could not get through, a net of shifting laser beams that would slice it and cook it and disintegrate it. It worked about as well as bullets do on Superman. And then it was upon us, knocking on the doors of Hell, hoping to leave the abyss in which it belongs.

It was very efficient by the time it reached the last containment that it got through. The general thought it was one of his soldiers on the other side, using a secret knock to say "I'm a human survivor" and that is why it thought, yes thought, that "Shave and a haircut" would also work to tell me to let it in. Or rather let it out, because if it got past me there is an unsuspecting world outside, unprepared for this nightmare, this unstoppable devil.

I won't let it out, in fact, I can't. I've shredded the keycard necessary to access the drive for the master computer. Even if I wanted to open this last door, there is no way for me to do so. It is also reset to my unique biometric scans and I assume it will eat me and lose that key also. If it somehow gets in here, it will find the last door cannot be opened. We're trapped down here forever, but to this thing, that isn't long enough.

That is why I am telling you about Livingstone, so that you will not be curious enough to see what is behind door number two. Never, ever, ever open that door, if you somehow can. It is sealed from the inside, but I fear some future generation might learn a way to open it anyway. I insist that you do not, or all will be lost. It sleeps down here, forever.

That is my greatest fear.