Oddly enough in The Adventures of Huckleberry Finn it starts as this amazing tale of a boy and his friend and ends with some weird satirical comedy.
From Wikipedia:
“Many subsequent critics, Ernest Hemingway among them, have deprecated the final chapters, claiming the book “devolves into little more than minstrel-show satire and broad comedy” after Jim is detained.[17] Hemingway declared, “All modern American literature comes from” Huck Finn, and hailed it as “the best book we’ve had.” He cautioned, however, “If you must read it you must stop where the Nigger Jim is stolen from the boys. That is the real end. The rest is just cheating.””