In "The Dreams in the Witch House," Walter Gilman, a student at Miskatonic University, finds himself drawn to rent an attic room in the infamous "Witch House" in Arkham, Massachusetts. This house carries a dark history, once housing the accused witch Keziah Mason who mysteriously vanished from a Salem jail. As Gilman settles in, he discovers a disturbing pattern of premature deaths among the previous occupants of the attic. However, the true horror lies in the dimensions of the room itself, which seem to defy logic and open the door to other planes or dimensions.

As Gilman delves deeper into the mysteries of the Witch House, he begins to experience surreal and unsettling dreams. In these dreams, he finds himself floating through ethereal landscapes of indescribable colors and sounds, encountering strange and ever-changing entities. These entities take the form of iridescent bubbles and shifting polyhedral figures, suggesting an otherworldly sentience. Moreover, Gilman's dreams intertwine with the past, as he encounters Keziah Mason and her bizarre familiar, Brown Jenkin. Gilman becomes convinced that these experiences are more than just dreams, that they hold a deeper connection to the supernatural.

The dreams intensify, leading Gilman to a shocking revelation. He dreams of signing the "Book of Azathoth" under the command of Keziah, Brown Jenkin, and the infamous "Black Man." In this nightmarish sequence, Gilman is transported to Azathoth's throne at the "Center of Chaos" and is coerced into participating in the kidnapping of an innocent child. When he wakes, Gilman finds mud on his feet, and soon, he discovers that his involvement in the kidnapping is reported in the city's newspaper. The horror escalates on Walpurgis Night when Gilman dreams of Keziah and Brown Jenkin sacrificing the kidnapped child in a ritual. In a desperate attempt to stop the atrocity, Gilman strangles Keziah, but Brown Jenkin brutally completes the ritual, escaping into an unfathomable abyss.

As Gilman awakens from his ordeal, he is plagued by an otherworldly sound that leaves him deaf. Sharing his terrifying tale with fellow boarder Frank Elwood, he realizes the true extent of the evil he has encountered. The horrifying climax occurs when Elwood witnesses Brown Jenkin emerging from Gilman's chest, consuming his former companion. The events within the Witch House continue to unfold as the landlord abandons the cursed dwelling, leading to its ultimate condemnation by the building inspector. Years later, during demolition, Keziah's skeleton, her books on black magic, a hidden chamber filled with children's bones, a sacrificial knife, and an unidentified metal bowl are discovered. Most perplexing of all is a stone statuette of the star-headed "Elder Things" from Gilman's dreams. These eerie artifacts are displayed in Miskatonic University's museum, leaving scholars and researchers befuddled by their inexplicable mysteries.

To further fuel the chaos and dread surrounding the Witch House, the attic's flooring reveals the skeleton of an enormous deformed rat with unusual human or primate characteristics. This shocking discovery shakes academia and disturbs the demolition workers to such an extent that they celebrate its demise by lighting thanksgiving candles within a nearby church.

"The Dreams in the Witch House" is a chilling tale of supernatural occurrences and nightmarish dimensions. Walter Gilman's descent into the horrors of the Witch House exposes him to a malevolent force that defies comprehension. Lovecraft's ability to craft a narrative that blends mathematical theories, folklore, and cosmic terror creates a unique and unsettling reading experience. As the artifacts discovered within the Witch House continue to baffle scholars and the memory of the deformed rat haunts the minds of those who encountered it, the legacy of Gilman's harrowing experiences will endure, reminding us of the nightmarish unknown lurking just beyond the walls of our reality.