The novel by Raymond Chandler was published in 1939 and was Chandler's first novel after a decade of writing short stories and a lifetime of doing unrelated things. By that time he was 51 years old. The Big Sleep, like all his subsequent novels, seven in all, features the iconic private eye Philip Marlowe.

The book itself, in my opinion, is not one of Chandler's best, but the ending is pure poetry.

What did it matter where you lay once you were dead? In a dirty sump or in a marble tower on top of a high hill? You were dead, you were sleeping the big sleep, you were not bothered by things like that. Oil and water were the same as wind and air to you. You just slept the big sleep, not caring about the nastiness of how you died or where you fell. Me, I was part of the nastiness now. Far more a part of it than Rusty Regan was. But the old man didn't have to be. He could lie quiet in his canopied bed, with his bloodless hands folded on the sheet, waiting. His heart was a brief, uncertain murmur. His thoughts were as gray as ashes. And in a little while he too, like Rusty Regan, would be sleeping the big sleep.

-- Raymond Chandler, The Big Sleep, 1939