I want a good classic novel that has a “message” or meaning behind it

I mostly read suspense mystery crime and some non fictional history stuff about medieval times but I want to get into something really good a classic like a Catcher in the Rye, or To Kill a Mockingbird. What's a good classic book that has a good meaning behind it? If it's in the suspense mystery genre that's a plus but any good read will do I want to start a good one it today if possible … Thank you in advance!