[The following excerpt is from Markheim by Robert Louis Stevenson]

. . . And as he sat thus, at once busy and absent, he was startled to his feet. A flash of ice, a flash of fire, a bursting gush of blood, went over him, and then he stood transfixed and thrilling. A step mounted the stair slowly and steadily, and presently a hand was laid upon the knob, and the lock clicked, and the door opened.

Fear held Markheim in a vice. What to expect he knew not--whether the dead man walking, or the official ministers of human justice, or some chance witness blindly stumbling in to consign him to the gallows. But when a face was thrust into the aperture, glanced round the room, looked at him, nodded and smiled as if in friendly recognition, and then withdrew again, and the door closed behind it, his fear broke loose from his control in a hoarse cry. At the sound of this the visitant returned.

"Did you call me?" he asked, pleasantly, and with that he entered the room and closed the door behind him.

Markheim stood and gazed at him with all his eyes. Perhaps there was a film upon his sight, but the outlines of the new comer seemed to change and waver like those of the idols in the wavering candle-light of the shop; and at times he thought he knew him; and at times he thought he bore a likeness to himself; and always, like a lump of living terror, there lay in his bosom the conviction that this thing was not of the earth and not of God.

And yet the creature had a strange air of the commonplace, as he stood looking on Markheim with a smile; and when he added, "You are looking for the money, I believe?" it was in the tones of everyday politeness.

Markheim made no answer.

"I should warn you," resumed the other, "that the maid has left her sweetheart earlier than usual and will soon be here. If Mr. Markheim be found in this house, I need not describe to him the consequences."

"You know me?" cried the murderer.

The visitor smiled. "You have long been a favourite of mine," he said; "and I have long observed and often sought to help you."

"What are you?" cried Markheim; "the devil?"

"What I may be," returned the other, "cannot affect the service I propose to render you."

"It can," cried Markheim; "it does! Be helped by you? No, never; not by you! You do not know me yet; thank God, you do not know me!"

"I know you," replied the visitant, with a sort of kind severity or rather firmness. "I know you to the soul."

"Know me!" cried Markheim. "Who can do so? My life is but a travesty and slander on myself. I have lived to belie my nature. All men do; all men are better than this disguise that grows about and stifles them. . . . I am worse than most; myself is more overlaid; my excuse is known to me and God. But, had I the time, I could disclose myself."

"To me?" inquired the visitant.

"To you before all," returned the murderer. "I supposed you were intelligent. I thought--since you exist--you would prove a reader of the heart. And yet you would propose to judge me by my acts! Think of it--my acts! . . . But can you not look within? Can you not understand that evil is hateful to me? Can you not see within me the clear writing of conscience, never blurred by any wilful sophistry, although too often disregarded? Can you not read me for a thing that surely must be common as humanity-- the unwilling sinner?"

"All this is very feelingly expressed," was the reply, "but it regards me not. . . . Shall I help you--I, who know all? Shall I tell you where to find the money?"

"For what price?" asked Markheim.

"I offer you the service for a Christmas gift," returned the other.

Markheim could not refrain from smiling with a kind of bitter triumph. "No," said he, "I will take nothing at your hands; if I were dying of thirst, and it was your hand that put the pitcher to my lips, I should find the courage to refuse. It may be credulous, but I will do nothing to commit myself to evil."

"I have no objection to a death-bed repentance," observed the visitant.

"Because you disbelieve their efficacy!" Markheim cried.

"I do not say so," returned the other; "but I look on these things from a different side, and when the life is done my interest falls. The man has lived to serve me, to spread black looks under colour of religion, or to sow tares in the wheat-field, as you do, in a course of weak compliance with desire. Now that he draws so near to his deliverance, he can add but one act of service: to repent, to die smiling, and thus to build up in confidence and hope the more timorous of my surviving followers. I am not so hard a master. Try me; accept my help. . . .

"And do you, then, suppose me such a creature?" asked Markheim. "Do you think I have no more generous aspirations than to sin and sin and sin and at last sneak into heaven? My heart rises at the thought. Is this, then, your experience of mankind? or is it because you find me with red hands that you presume such baseness? And is this crime of murder indeed so impious as to dry up the very springs of good?"

"Murder is to me no special category," replied the other. "All sins are murder, even as all life is war. I behold your race, like starving mariners on a raft, plucking crusts out of the hands of famine and feeding on each other's lives. . . .

"I will lay my heart open to you," answered Markheim. "This crime on which you find me is my last. . . . I have wandered a few years, but now I see once more my city of destination."

"You are to use this money on the Stock Exchange, I think?" remarked the visitor; "and there, if I mistake not, you have already lost some thousands?"

"Ah," said Markheim, "but this time I have a sure thing."

"This time, again, you will lose," replied the visitor quietly.

"Ah, but I keep back the half!" cried Markheim.

"That also you will lose," said the other.

. . .

(Robert Louis Stevenson, Markheim (1885) http://www.online-literature.com/stevenson/2058/

[How does it end? That’s up to you.]