Instead of frantically searching the internet for a summary and a last minute "wing-it" book report (the kind you turn in hoping and praying it doesn't sound like you didn't actually read the book) I think most teachers on this site *we question answerers are pretty much ALL teachers* would encourage you to go to your teacher tomorrow and confess that you have not read the book.
I'm not speaking for everyone when I say this, but as a teacher who has dealt with the students who turn in the "Sparknotes version" of a book report and those who come clean and just ask for more time, I'm more apt to forgive and provide an option of redemption for the second student. What you need to understand is that your teacher will know that you did not read the book. Even if HE or SHE has not read the book, most, if not all literature teachers are pretty good at analyzing tone. If you have not read the book, this will come out in the tone of your book report. Your teacher might not even directly address it, but he or she will know.
Now, if you do choose to take the road of integrity here, understand there is (believe it or not) a bad and a better approach.
BAD approach: addressing your teacher one-on-one JUST before or JUST after the bell rings to start class. You've already screwed up - don't take up your TEACHER'S class time to fix it.
BETTER: email your teacher tonight and explain the situation. Own up to laziness if that is the only excuse. As cliche as it sounds, honesty truly is the best policy.
BETTER: wait until the end of the day (or perhaps the down time at the end of class) and ask to talk to your teacher one-on-one. Explain in person.
Be prepared to receive neither forgiveness NOR redemption. After all, your entire class had the same amount of time and how is it fair to give you an extension? However, most reasonable teachers will look at such a situation and work out a plea bargain (as they say in the legal world). If I was your teacher, I'd ask for a reasonable amount of time for you to get the book read. Let's say you can do it over the weekend. I'd then say, "Get it done and blow me away with the book report. You won't get full credit, but you won't get a zero either. We'll deal with the grade when I see the report... AND YOU BETTER READ THE BOOK." I would say the last part with a stern voice and smile.
Don't fake it. Just don't. Even if you do get away with it this time, it isn't worth the reward that will tell you "It worked last time it will work again." Because faking it rarely works, and it's when it counts the most that it will get you.