The narrator goes and visits his friend because he mailed to him, A letter, however, had lately reached me in a distant part of the country - a letter from him.
While talking together the narrator learns that Usher and his sister are sick.-disease of lady MadelineI shall perish
In the movie you could see the house shaking (I cant find text evidence)
Madeline dies, Usher has the narrator help with the tomb. -the lady Madeline was no more-intention of preserving her corpse for a fortnight.
-there did stand the lofty and enshrouded figure of the lady Madeline of Usher-bore him to the floor a corpse, and a victim to the terrors he had anticipated.
Madeline comes back for Usher and they die together, The house starts shacking and the narrator runs
After the Usher's die the house starts to shake
The narrator leaves the house, the radiance was that of the full, setting, and blood red moon