What I try to do is write a story about a detective rather than a detective story. Keeping the reader fooled until the last, possible moment is a good trick and I usually try to play it, but I can't attach more than secondary importance to it. The puzzle isn't so interesting to me as the behavior of the detective attacking it.

Listen, darling, tomorrow I'll buy you a whole lot of detective stories, but don't worry your pretty little head over mysteries tonight.

Nick: "Don't you think maybe a drink would help you to sleep?" Nora: "No, thanks." Nick: "Maybe it would if I took one.

The people who lie the most are nearly always the clumsiest at it, and they're easier to fool with lies than most people, too. You'd think they'd be on the look-out for lies, but they seem to be the very ones that will believe almost anything at all.

When a man's partner is killed he's supposed to do something about it. It doesn't make any difference what you thought of him. He was your partner and you're supposed to do something about it. Then it happens we were in the detective business. Well, when one of your organization gets killed it's bad business to let the killer get away with it. It's bad all around-bad for that one organization, bad for every detective everywhere. Sam Spade

He felt like somebody had taken the lid off life and let him see the works.

To get what he wanted, a man had to give other people what they wanted.