The old man's caretaker had snuck into the old man's room as he slept. The man's blue eye had been bothering him for a while now. The caretaker thinks that it's more than just an eye; it's a curse.
The Tell-Tale Heart
That eye. That cursed vulture eye.
Now that eye will bother me no more.
The caretaker had killed the old man, resolving his issue with the eye. He then chops the body up and puts it in a suitcase under the floor, the heart right beneath him. The problem will never come back to haunt him ever again. Or, will it?
The caretaker can hear the heartbeat of the dead man ringing in his ears, like a clock enveloped in cotton. The pulse was driving him insane to the point where he almost couldn't take it anymore.
After hearing a scream, a neighbor next door called the police to see if everyone is okay. The murder was still not known about since the caretaker wanted to keep it a secret. Yet. Nobody had found out what had happened to the poor old man yet.
Did I hear a scream? I'll call the police just to make sure everyone is okay.
Hello, sir. We had come after a report by your neighbor of a scream nearby so we wanted to check and see if you're okay.
Yes, officer, I am perfectly fine. Would you like a cup of coffee? After so much hard work, you must need it.
Though he played it off fine, he can still hear the old man's heartbeat. He tried to keep himself calm in front of the police, but he could hardly take it any longer. But he can't tell them, he'll get arrested!
The heartbeat! I can hear his heartbeat!
You're under arrest, sir!
I can't take it anymore, I can hear his very pulse! I killed the man, officers! It was me! His cursed eye made me do it!
The man had gone mad, screaming to the officers, confessing his crime. After attempting to put on a facade to mask his heinous crime, he fell through by hearing the sound of the dead man's heartbeat replay in his head. The officers then arrested him on an act of murder.