James Joyce's "Finnegans Wake" is sometimes credited as a masterpiece, and sometimes viewed as an inexplicably long, overly obscure, completely unreadable tome. Both, to some degree, are true.
Firstly, do not even attempt this book unless you have vast amounts of time in which to do so, almost limitless patience, and, dare I say, more than a little intellectual capacity! The plot, if such there is, consists of one day in the life of an Irish family, within which the father, HCE, commits some sort of crime and the mother, ALP, seeks to acquit him. Beyond that, the details are impossible to be clear about. Joyce writes largely in non-existent words, portmanteaus and hybrid puns incorporating a wide variety of languages (some scholars estimate seventy or more, but nobody is sure). Entire chapters can pass without any reader (yours truly included!) understanding what's happened, or even who was involved, or where anything is.
Does this matter? Can "the Wake" be read without any knowledge of what's going on?
Actually, yes! The best way to read is to abandon every convention you ever knew: don't go from page to page following plot, character and so on, but just drift through the book, letting the sounds of the language wash over you. Best of all, when you do understand a brief, tangled reference, it's like a glimpse of light among the darkness, and you can allow yourself a brief smile before being swallowed up by the virtuosic confusion once more.
And trust me on this... when you get to the end, it's impossible to come out of the other side feeling anything other than that Joyce was an absolute genius. You have no idea why: odd, but so true.