Once or twice, I heard Gaiman's
Stardust described as fantasy for adults because it had all of one awkward (but still titillating) sex scene. I used to agree with that sentiment, but now I think otherwise.
When you were young, you probably started to read with
Redwall or
Harry Potter. Then, in your teen years, you develop the rebellious attitude shared by all teens and search for something "darker" and "grittier". Here is where you start reading things like
Sword of Truth or
Dresden Files. Once you become a legal adult (or close to one), you realize you had no taste as a kid and you start reading "real books", sometimes abandoning genre fiction entirely. Maybe a little further you get your head out of your ass and go back to fantasy/sci-fi with a fresh, unprejudiced eye and you start appreciating novels like Pratchett's
Night Watch for what they are, "real" topics disguised as children's novels.
With
The Ocean at the End of the Lane, Gaiman takes this progression one step further, into a territory I did not know existed.
The Ocean at the End of the Lane is about a man, in his 40s, reminiscing about the time he was a protagonist in a typical Gaiman novel. However, unlike Tristran Thorn, Richard Mayhew, Shadow or Fat Charlie, the protagonist of
The Ocean at the End of the Lane was only 7 at the time of his encounter with Gaiman's trademark "world behind the world". For this reason, and others, there were a two key differences between him and Gaiman's other sameplot protagonists:
1) He readily accepted that he was entering some kind of fantasy story, instead of being incredulous for half the book, seamlessly melding the fantasy world with his reality in a way only children are capable of. This is exemplary of the idea of "childhood innocence", which, honestly, is more believable than the skepticism of fictional adults when confronted with the strange and unreal.
2) He didn't have some kind of destiny given to him by birthright to fulfill. For him, it was just another faded childhood memory, which eventually blurred into all his other childhood memories but nevertheless served to shape the man who he would become. This is consistent with reality, because we all share vaguely remember childhood memories that, when examined closely, were probably responsible for our becoming who we are now.
Though the story is told from the perspective of a child, its real purpose is to highlight the differences between the way a child experiences the world and the way an adult experiences it. This is why framing story exists, without which
The Ocean at the End of the Lane would probably fall firmly under YA like
The Graveyard Book. Through this contrast, however, Gaiman makes the reader aware of the kinds of things they lost and gained on their way to adulthood.
The Ocean at the End of the Lane is more about adulthood than most other stories (especially Gaiman's other stories) I've ever read. I would go so far as to say that this is the only book I know that tries to convey what it means to be an adult, rather than being a childhood fantasy wrapped up and decorated with "adult" flavorings.
One of the main reasons Gaiman is my favorite author is because whenever I finished one of my stories, I tend to undergo a period of reflection on my reality and whether it may be overlaying a more fantastic reality like the ones Gaiman crafts. This book went beyond that, and made me question whether my enjoyment of Gaiman's previous novels (and others) was because of my "maturing tastes", or because I was trying to recapture my childhood and trying to escape further from reality as I know it.
tl;dr: The Ocean at the End of the Lane is good, but I would not recommend it to anyone unless they were:
a) A fan of Gaiman's particular kind of prose.
b) In need of a literary existential crisis.
EDIT: And, despite being exceptionally short, it is probably more dense and meaningful than most other fantasy/magic realism stories. Because really, to a child's eyes, every fantasy story is magic realism.