So, have you heard of the Battle of Rorke's Drift, which took place in 1879 in South Africa? That's the battle in which about 150 British soldiers hanging out in a "garrison" (read: old trading post with no real defenses) managed to survive a two-day attack by 3,000-4,000 Zulu troops. It's a remarkable story--I mean, yes, the British were pretty much doomed in South Africa and holding onto Rorke's Drift didn't actually help with that, but from a tactical perspective, it was pretty amazing.
And it was made into a pretty amazing movie called Zulu, which among other things made Michael Caine a star.
And yesterday I read the book Zulu: In Space.
OK, it wasn't really called that. But that's what the book was--a retelling of the Battle of Rorke's Drift in space with aliens. The Zulus were played by the really alien aliens, and the British were played by the humans and their allied aliens, and I just know we could have a long discussion about post-colonialism, post-post-colonialism, post-post-post-colonialism, and whether we should still be offended by this sort of thing or if we're all over it now.
But was it a good book? Honestly, I can't say--I didn't enjoy it nearly so much once I figured out it was Zulu: In Space. I have a good memory for stories (to compensate for my terrible memory for names, I guess), and once I realized what I was reading, everything became dull and predictable, especially because the book followed the (extremely memorable) movie very closely. So reading it was like: Oh, here are the two wounded guys who together make one soldier; oh, now the Zulus--I mean, the aliens--have gotten over the wall, that's going to suck; oh, now the British--I mean, the humans--are singing back, it's about time.
There was also the knowledge that surprises weren't going to come from certain sources. When the humans & friends find a pair of weird alien buildings on this weird alien planet to occupy, they wonder why the buildings are there and why they are arranged the way they are arranged. At first I wondered, too, thinking this was a set-up for some delightful or dreadful surprise, but of course the buildings were arranged that way because that's the way they were arranged in South Africa in 1879. What, you were expecting something interesting, or maybe just something germane to the story?
This doesn't just happen with books based on historical events--although I've read quite a number of fantasy/alternative-history/steampunk books that devolve into history textbooks (that I've already read, thanks). It happens with books based on earlier literature--when King Lear shows up, the reader is not exactly shocked when it turns out that Princess Cordelia is a peach but that her sisters are not so nice.
I think it's a matter of letting the tail wag the dog--it's fine to be inspired by true events/other literature, but if you're just retelling someone else's story, why bother? Rosencrantz and Guildenstern Are Dead is respected because it's not Hamlet: In Space or Hamlet: The Musical or Hamlet: The Version More Consistent with Tom Stoppard's Political Beliefs. Even something as fundamentally silly and commercial as the 2007 movie version of Beowulf isn't about a super-duper guy who fights a monster and the monster's mother, and then finally bites it facing a dragon--it's about how that legend came to be. (And now I'm reading the Wikipedia entry about that movie and realizing that it was written by Neil Gaiman. Ex ungue leonem!*)
(* Before you start thinking that's totally unwarranted praise given how noisy and over-the-top the Beowulf movie was, I studied Anglo-Saxon poetry for a year in college, and it's obvious that the movie was written by someone who is both familiar with the poem and with the language--there's a lot of clever transitioning between Modern English and Old English.** Considering that most of the time Hollywood produces laughably ignorant crap like "When you taught Beowulf, did you make the kids read it in the original Middle English or did you use a translation?"--which is not only dumb because Beowulf is Old, not Middle English, but also because unlike Middle English, Old English is incomprehensible to speakers of Modern English, even the alphabet is different, so getting snippy because a high-school teacher teaches Beowulf in translation simply indicates that President Bartlet is an overly-demanding asshole with a gigantic stick up his butt--I was pleasantly surprised.)
(**OK, this is hard-core geekery about the use of Old English in the movie version of Beowulf. Wikipedia says that Grendel (the monster) speaks Old English, but that's not quite true. Grendel speaks Old English words, but he does not speak Old English.
What do I mean? Well, let's look at a Modern English sentence:
Beowulf tore off Grendel's arm with his powerful hands.
You understand that, right? You know who did what to whose arm and with what he did it. And you know that because of the order in which the words appear. Word order is key to Modern English.
Word order is irrelevant to Old English. Instead, they used word endings to tell you what was the subject, what was the object, what was the indirect object, etc. An adjective like "powerful" would have a different ending depending on whether you meant that Beowulf's hands were powerful or that Grendel's arm was powerful or that Beowulf or Grendel were just generally powerful.
Assuming you gave every word the correct ending, you could mix up those words and not change the meaning of the sentence. In other words, in Old English:
Hands with arm his tore Grendel's Beowulf powerful off.
His powerful arm off Grendel's with tore Beowulf hands.
With his off Beowulf hands Grendel's tore arm powerful.
Grendel's tore arm with powerful off hands his Beowulf.
would all make total sense, and they would all mean "Beowulf tore off Grendel's arm with his powerful hands."
That's a big part of the reason Old English is so freaking incomprehensible to Modern English speakers--when a sentence begins "With and what weather with held he hot the that and the though," the speaker of Modern English pretty much throws in the towel. (And the Anglo-Saxons did that sort of thing all the time, because their poetry didn't rhyme, it alliterated. Since word order didn't affect meaning, it made perfect sense to organize their sentences by grouping together words that started with the same letter.)
What they did in the movie version of Beowulf was have Grendel use Old English vocabulary and Modern English syntax. So when Grendel says, "Mother, the man hurt me," it sounds a little weird ("Muther, tha maen hurt mea" or whatever--I'm not looking it up), but you can understand him. Which just goes to show how important word order is to us--if, instead, he said "Man me mother hurt the," you'd have a much harder time understanding him, even though those are Modern English words.
For the record, later in the movie there's a couple of minstrels who are speaking proper Old English (in fact, they're reciting the original Beowulf). It's not even recognizable as English.)