The narrator receives an invite from his old pal, Roderick Usher. Roderick states that he has an acute body illness of a mental disorder. So, the narrator decides to visit his friend and see his well-being.
The narrator sees that Usher is completely different from what he was like before. He remembers him as an energetic and happy kid, but now see's almost a ghost-like version of Usher.
Roderick's sister Madeline has cataleptic, death-like trances as told by Roderick to the narrator.
Usher believes that his sister has finally passed, so he places her in a tomb until she is ready for proper burial. Which would be in two weeks.
After placing Madeline into the vault, a storm breaks out and scares Roderick. The narrator beings to read to Roderick to calm him down.
A scream is heard as they're concluding their reading and Roderick tells the narrator that he's been hearing noises from his sister's tomb and fears that he may have buried her alive. Then the door flies open and a bloody Madeline rushes towards Roderick.