Answer:
The theme, simply put, is fear and its effect on one's mind - particularly a fear of the unknown.
Explanation:
"The Premature Burial" is a short story about one man's extreme fear of being buried alive. He struggles from an internal conflict (him vs. his mind), as he obsessively imagines himself being buried alive over and over. It is worth noting that the narrator frequently suffers from catalepsy (loss of sensation and consciousness similar to death) hence, fearing a cataleptic state will make others believe he is dead.
You would have to tell us what the sketches are
