By F. Scott Fitzgerald
I love this book because it's the gold standard for unreliable narrators. Nick Carraway tells us the story of Jay Gatsby and Daisy; he tells us he isn't going to pass judgment on the characters, but he manages to overlook things, like Gatsby's bootlegging trade and that Daisy's husband is cheating on her. The result is that the character Gatsby remains a mystery long after you've finished the book.
One scene I remember is Daisy in Gatsby's bedroom, exclaiming over his beautiful shirts. It's this great moment of crisis for her: She spurned the man she loved because he didn't have money, and now he does. She realizes her life could have been very different, and she can't even articulate that to herself.