The following letter was discovered in Professor Soames' personal effects, filed within a leather portfolio marked "NEUROHYPNOTISM - CORRESPONDENCES OF CONCERN." The paper shows water damage, and the ink has faded in several places. It appears to have been read and re-read many times, the creases worn soft.

15 March, 1862
Ryefield House
Manchester

My Dear Professor Soames,

I write to you in haste and with considerable trepidation, for I fear my recent experiments have led me into waters far deeper and more terrible than any man of science should dare navigate. You, who have pursued similar inquiries into the liminal states of consciousness, must understand the profound danger I now perceive—though I pray you have not ventured so far along this path as to encounter what I have encountered.

Your last letter asked after my work with deep cataleptic trances and the curious phenomenon we discussed at the Royal Society meeting—namely, whether the mind in such states might touch upon dimensions or planes of existence normally barred from waking consciousness. At the time, I confess, I viewed your questions with academic enthusiasm, flattered by your interest in my theories. Now I wish I had never responded. I wish I had burned your letter and my own notes and retreated to the safer territories of therapeutic hypnotism for toothaches and nervous complaints.

But I did not. And neither, I suspect, did you.

Three weeks ago, I successfully induced a trance state in my subject—a young woman of robust constitution and impressively placid temperament, a parson's daughter from Leeds with no history of nervous disorders or hysteria. I shall not record her name here, for reasons that will become apparent. The trance was deeper than any I had previously achieved. Her breathing slowed to near imperceptibility. Her pulse became so faint that my colleague, Dr. Richardson, feared we had lost her entirely.

What followed I can scarcely describe without sounding like a candidate for Bedlam.

She began to speak—not in English, but in a language utterly foreign to her waking knowledge. The sounds were wet, somehow. Guttural and fluid at once, like words spoken underwater or by a throat not quite human in its configuration. Dr. Richardson suggested glossolalia, the speaking in tongues reported in certain religious enthusiasms, but this was different. This had structure. Grammar. Syntax. This was not ecstatic babbling but coherent speech in a tongue older than our civilization.

Richardson transcribed what he could, though the sounds defied our alphabet. When we later consulted a linguist of my acquaintance—a fellow who has studied the most obscure dialects of the Pacific islands—he blanched upon seeing the transcription. He would tell us nothing of what he recognized, only that we must destroy the document immediately and never attempt such an experiment again.

We did not destroy it. God forgive us, we did not destroy it.

The young woman, upon waking, remembered nothing of what she had said. But her eyes had changed, Soames. The color remained the same, yes, but the shape of the pupil—for just a moment, as she emerged from the trance, was wrong. Vertical. Slit like a cat's or a serpent's, and in that instant before they returned to their natural roundness, I saw in those eyes an intelligence that was not hers. Something looked out at me through her face, and it was amused.

She complained of pain in her chest and back. Richardson examined her and found nothing. I sent her home with assurances and a guinea for her trouble. The next morning, I received word that she had been discovered in her bed, drowned. There was no water in the room. Her lungs were full of seawater, and her nightgown was wet with it, and the sheets beneath her were soaked through to the mattress. The window had been locked from the inside.

But that is not the worst of it.

When the coroner examined her body, he found marks upon her ribs. Incisions, he called them, though they appeared to have been made from the inside out. Twelve marks, six per side, each approximately three inches in length. The flesh around them showed signs of inflammation and new tissue growth, as though her body had been attempting to develop structures beneath the skin. The coroner's assistant—a man who had served in Her Majesty's Navy and seen his share of grotesquerie—said they looked like nothing so much as gill slits on a fish.

I include this detail because you must understand the gravity of what we have disturbed. This is not mere somnambulism or hysterical conversion. This is not the mind playing tricks upon the body through the medium of suggestion. Something reached through the trance state and touched her. Something claimed her. And I fear it was something that has been waiting a very long time for the door to be opened.

Since that night, I have been troubled by dreams of a vast and lightless ocean. I dream I am swimming in waters so deep that no sun has ever penetrated them, and all around me move shapes of such size and strangeness that I wake gasping, my sheets damp with sweat that smells of brine and rotting kelp.

Three nights ago, I woke to find my nightshirt soaked through. Not with sweat, Soames, but with seawater. I live fifteen miles from the nearest coast.

I am writing to you because I believe you have pursued similar lines of inquiry. Your research into ancient oceanic cults, your interest in pre-Celtic religious practices along the Irish coast, your questions about the neurological effects of hypnotic suggestion—these are not idle academic curiosities, are they? You have found something. Or something has found you.

I beg you, if you have begun such experiments, cease immediately. Burn your notes. Destroy your transcriptions. There are doors in the human mind that must remain closed, not because we lack the courage to open them, but because what waits on the other side is not meant to share our world.

The old religions knew this. The old priesthoods understood that certain rites were not abolished by Christianity because they were false, but because they were true—and true in ways that threatened not merely the soul but the very integrity of the human form.

I have contacted a colleague in America, a Dr. Armitage in Arkham, Massachusetts, who has studied certain ancient texts that reference these matters. He has confirmed my worst suspicions. There are entities, Soames—intelligences vast and ancient and utterly inimical to human life as we understand it—that exist in the deep places of the ocean, and they are capable of responding to the human mind when it is rendered sufficiently open and vulnerable. They can touch us. They can change us. They can prepare us for reunion with them.

Dr. Armitage used a phrase that has haunted me since I read his letter. He said these entities seek to "reclaim what was promised to them." When I asked what this meant, he would say only that there are old debts, old compacts, older than history, and that certain bloodlines carry the mark of these agreements whether they know it or not.

I fear I may carry such a mark. The parson's daughter certainly did, though neither she nor her family had any knowledge of it. It expressed itself only when I lowered her conscious barriers through hypnotic suggestion. I opened the door. I let it see her. And it recognized what she was and claimed her for its own.

My nightmares grow worse. I dream of a city beneath the waves, its architecture wrong in fundamental ways—angles that should not be possible, corridors that extend beyond the limits of physical space, towers that spiral down into abysses where things vast and patient wait. I dream of transformation. I dream of breathing water and finding it sweet. I dream of a voice that speaks my name with what almost sounds like love, if love can be cold and ancient and utterly without mercy.

This morning, I found myself standing on the shore near Southport with no memory of how I arrived there. I had walked twelve miles in my night clothes, and my feet were bleeding, and I was weeping, though I could not remember why. A fisherman found me and brought me home. He said I was calling out to the sea in a language he did not recognize.

I am beginning to suspect that

The letter ends here, mid-sentence, with a trailing ink stroke as though the pen had been dropped suddenly. In the margin, in a different hand (presumably Professor Soames' own), is written a single word:

"Claimed."

Beneath this, in the same hand but written years later (the ink noticeably darker), are the words:

"The same fate awaits us all. We were promised. We were marked. The Bride must come to the Water. The transformation cannot be prevented, only delayed. L. knows this. L. has always known. She prepares the way. December 21st. Solstice. The door opens fully. I tried to stop her. I tried to warn them. But I am already becoming. My veins spell out the invocation. My skin remembers the water. Soon I will remember too, and then I will stop fighting. We all stop fighting eventually."

The rest of the page is blank.