What is the plot of the short story "The Black Cat" by Edgar Allan Poe?

Edgar Allan Poe's short story "The Black Cat" was published in 1845. Written in first-person point of view, it is the story of one man's descent into madness as a result of an addiction to alcohol. It bears many similarities to Poe's story "The Tell-Tale Heart." 
The narrator begins by describing his gentle and kind nature. He has a great affinity for animals. He and his wife have a collection of animals, including a large black cat named Pluto. The narrator describes Pluto as his favorite of all the animals. The narrator is the only one who feeds this cat, and the cat follows him nearly everywhere he goes. 
The narrator describes the disintegration of the affectionate relationship with the cat as a result of his growing addiction to alcohol. His alcoholism changes his demeanor, as well as his feelings for the cat. The narrator, returning home from a night of drinking, thinks the cat is avoiding him, and for that reason, he grabs the cat. Pluto reacts by biting him on the hand, and the narrator flies into a rage. He takes out a pen knife and gouges out Pluto's eye. 
After this, the narrator describes feelings of great remorse, but confesses the remorse never really fills his soul. The cat recovers but avoids the narrator. The narrator describes his descent into what he calls "a spirit of perverseness." He claims he causes further harm to the cat based on his perverse human nature. 

Yet I am not more sure that my soul lives, than I am that perverseness is one of the primitive impulses of the human heart—one of the indivisible primary faculties, or sentiments, which give direction to the character of Man. Who has not, a hundred times, found himself committing a vile or a silly action, for no other reason than because he knows he should not?

The narrator hangs the cat from a tree in the garden. He explains that he did it for no other reason than that he knew that by harming the cat he was committing a sin. That night, his house is destroyed in a fire. The narrator is careful to point out there is not a likely correlation between these two events. The house is a total loss except for one wall, the wall on which the narrator's bed rested. The neighbors gather around the wall and marvel at what they see. The narrator discovers there is an image of a cat on the wall. He describes this image as containing so much detail that he compares it to a bas relief. The image contains a noose around the cat's neck  
Insanely, the narrator reasons that since neighbors gathered in the garden where the cat was hung, one of them must have cut the cat down and threw it in the window of his bedroom in order to warn him of the fire. He thinks the lime of the still-wet plaster and the ammonia from the carcass could have caused the picture of the cat. 
Later, the narrator is drinking, and he sees a cat sitting on a barrel of gin. The cat is a clone of Pluto in all ways except a white mark on his breast. The cat shows the narrator great affection and follows him home. In the morning, he sees the cat is missing an eye. He begins to dread the animal. The cat follows him everywhere, rubbing up against him constantly, which causes him to trip frequently. 
One day, he goes down to the cellar for an errand. His wife accompanies him, as does the cat. The cat nearly trips him on the steep stairs. He is incited to rage and raises an ax to kill the animal. His tender-hearted wife raises her hand to stop him, so he plunges the ax into her head instead. 
At this point, all confessions of remorse are gone from the narrator's speech. He sets about describing how he will dispose of the body. He decides to place his wife's body in a wall and plaster over it. He accomplishes the feat so well that the police suspect nothing when they arrive. He nearly gets away with murder until the howling begins in the wall. It sounds like the wailing of a child, and when the police break into the wall, they find the woman's body and a black cat sitting on her head. The cat is all black except the white outline of a noose on its neck.