The references are particularly important if the fandoms in question involve either fantasy or science fiction elements. A crossover between, say, JAG and Due South would be relatively easy once you figured out a plausible reason to have Harm interacting with the Chicago gang. Hell, a crossover between the Blues Brothers and Due South could theoretically be arranged if you were willing to fiddle with the time stream a bit. Fandoms that rely primarily on real-world rules are easy to combine once the premises have been successfully bridged into each other. Everyone knows how the real world works. If you're going to cross fantasy realms, however, you have to decide what the deal is with magic. Unless you're crossing Marion Zimmer Bradley's The Firebrand with Mary Renault's The King Must Die / The Bull From The Sea, you are almost never going to find two fantasy authors whose take on magic, gods, artifacts, etc. work the same way. (Bradley was drawing heavy inspiration from Renault, and said so in her intro to The Firebrand.)
Crossing the Belgariad and Lord of the Rings, for some reason? Then you're going to have to figure out whether the Will and the Word can be used in Middle-earth, and how that sorcery is affected by the change of setting. Crossing Mercedes Lackey's Elemental Masters books with Charmed? The powers of the Charmed Ones are very different from those of people whose workings mostly flow through the essences of elemental spirits. You are going to have to figure out why, and either explain why, or show the conflict in action. In Hellblazer: Hogwarts, John Constantine still has his ability to manipulate the force of magic- but because he's in the Potterverse, it doesn't work right. He can't summon demons or angels because there's nothing to be summoned, and he can't work small spontaneous non-ritual magics without engendering a tremendous migraine unless he uses a wand. The world itself expects magic to be a certain way, and so he has to play along. Were he to land in Middle-earth himself he'd probably be even more screwed, given that the only known canon magic manipulators in that universe are all non-human (with the possible exception of Malbeth the Seer).
Same deal for science fiction. Say Jaxom of Pern foolishly persuaded Ruth to go between using a picture some colonist left in a recently unearthed archaeological dig, and somehow wound up in Star Wars. Do Jedi mind tricks work on telepathic dragons? The red-headed Comyn telepaths in the Domains of Darkover can do amazing things, but the majority of what they can do requires Darkovan matrix gems in order to function. Thrust one of them into the X-Men universe, and they're going to wind up with some pretty weird reactions to the redheaded, telepathic, telekinetic, no-matrix-gem-anywhere-in-sight-unless-you-count-that-damn-M'Kraan-Crystal Jean Grey. Given the vastly different ways in which the two fandoms handle faster-than-light travel, exactly what are the consequences of the Starship Enterprise launching itself into warp speed and going through a Babylon 5 jumpgate? (My guess is, it's like putting a portable hole into a bag of holding, but that's just me.) Figure these things out before you write, and keep your interactions consistent. There should be a reason behind the way things are!
The next thing to do, now that you've got your stuff neatly lined up, is get a piece of blank paper or fire up your word processor and write- not your story. Not yet. Start by writing down the idea or plot that you want. Write down the characters that you want to see involved in this plot, and any events or incidents you definitely want to see happen. Spend some time thinking about how to fit these things together. From this general listing, you can then write out your outline- either for the whole fic, or for the individual chapter you plan to work on first. It helps, when you're writing these things, to know where you're going and what you're doing next. The outlines and lists don't have to be ironclad, of course. If you're banging along and you realise that there's an event you'd planned to include that doesn't feel quite right, by all means leave it out! If you suddenly realise that it would be absolutely perfect to have the unbearable tension between Hellboy and Severus Snape defused by Crabbe wandering through the background singing 'Found A Peanut', then put it in (assuming that it really would defuse the tension and not merely engender a spate of 'wtf?' from the readers). The outline is there to remind you which way to go, and to make sure that you've got a coherent plan for your story. This is especially important in crossovers, because it's very easy to say 'I'm already doing something unlikely by my mere premise, I can get away with more'.
Here's a hint: you can't.
Crossovers have got a very bad name due to the sheer number of people writing crappy crossover fic. Some of it's merely uninspired. Some of it's genuinely bad. Some of it is nothing but an excuse to get Hermione Granger in bed with Legolas. If you're going to write a crossover fanfic, a tremendous number of your readers are going to come to it assuming the absolute worst. You are going to have to do better- you're being held to a higher standard by the nature of your fic. At least try to live up to that.
Part of doing so is keeping your characters in character. You're already screwing with their universes. Something should stay the same as it was in the original fandoms, and that something is the characters. Gojira might be in a world where Cthulhu is rising to devour everything in his path, but that doesn't make the atomic dragon any less of an elemental force of destruction. He's just going to be venting his wrath on the unnatural horror from beyond the stars, rather than on particularly ugly bits of Tokyo architecture. Freddy Krueger might be competing with Jason Voorhees for teenagers killed, but he's not going to go all grim and silent as a consequence. Neither is he going to come over all sympathetic towards the Hockey Mask Killer's victims. No, he's going to be snarky, nasty, overconfident, and easily provoked into rages where he does something stupid- just like in his own movies. Severus Snape might be fighting John Constantine in a wand duel, but that isn't going to make him any nicer, or any less of a consummately scary magician. He's still going to be Snape, and Constantine's still going to be Constantine. If you want people to like your crossover fic, you have got to write the characters the same way the original author / screenwriter / whatever did.
Should the character go through events or circumstances that would give them a believable reason to change their ways, then by all means, let that happen- but it should be within reason. Even if the wand duel impresses the living hell out of Snape for some reason, he isn't going to smile about it. He's not even going to congratulate his opponent. There might be a cold, respectful nod, or possibly a twitching of the corners of the mouth. That's all you'll see. Maybe later in the fic he'll indicate to someone that Constantine isn't a total incompetent, or he'll dock a House some points because he heard one of the students back-talking the new professor when Constantine wasn't listening. That's what you can expect when Snape starts to approve of someone he previously found distasteful. Keep your changes within reason and your audience will thank you for it.
(Speaking of keeping characters in character. . .
As regards the inevitable topic of romance. I don't generally write that, be it between a male and a female, between a female and a female, or between a male and a male. I've written smut, but it was for private consumption. I cannot advise you on the wisdom of putting slash or femslash or whatever elements into your crossover fic, because I don't even write that stuff when I'm not doing crossovers. I do suggest you stick to writing what you're good at, be it gen or het or slash or girl on girl on girl on girl on guy on sheep, and that you keep in mind whatever the local obscenity laws are with regards to people of your age group.)
Now that you've slogged through all of the rules, suggestions, etc. and written your crossover fic, you still aren't done. Spellcheck, of course. If you haven't got a spellchecker on your computer for some reason, find one on the Web- they exist. They are your friends. Grammar checkers, however, are not your friends. Grammar checkers on computers are more painful than helpful, in my experience. You want your grammar checked without the tone of your story being mutilated? Get a beta reader. Get someone who knows one or both fandoms intimately and have them read your story. Ask their advice. Ask them where changes need to be made. Then follow through on that advice. You might well think your stuff is the greatest in the world, but take it from me, you will be better off if you have someone else look at it first. If you're planning to have anyone in the entire world who is not you read your story, then you need to have someone who is also not you read it and tell you if they spot mistakes or problems. I do it. J. Michael Straczynski did it (though in his case it wasn't so much a 'beta reader' as a 'script editor'). There is no shame in having someone else check your work over and make suggestions on both plot and grammar.
Yes, it's a pain in the arse, but J. Michael Straczynski is beloved by fans the world over for his work on Real Ghostbusters, Babylon 5, and Amazing Spider-Man. He didn't consider it too much of a pain in the arse. Learn from the nice man's example.
I'm trying to think of what else to say, because this is the point where I normally post my stuff to the Net in one fashion or another. Most often I post my fic to my LJ and wait for comments before making a few final edits and submitting to a fanfic archive site like FictionAlley or Fanfiction.net. About the only other stuff I can add here is random bits of advice that didn't really fit in with the rest:
- Many people will tell you that crossovers work better when they are humorous or parody, rather than straight-up drama. This isn't always the case, as comedy is bloody hard to do right without taking an unexpected turn into Just Plain Stupid.
- That being said, both Who Ya Gonna Owl? and Evidence were written (are still being written in the case of WYGO?) because the concepts, for me, violated Skippy's List Rule #87: if the thought of something makes me giggle for more than fifteen seconds, I am to assume I am not allowed to do it. If you can take something that's Just So Damn Wrong and write about it with a straight face, giving it the same respect as Nicholas Meyer gave Sherlock Holmes in The Seven Per Cent Solution, then by all means give it a go. Be aware that other people may not find it as funny as you, though.
- Tread very, very carefully around the impulse to create original characters. You're already working with two entire fandoms here. Throwing in totally new people as anything other than background material (Caleb Augustus Blodgett, the Ancient Runes teacher, and Sophronia Toops in Muggle Studies are examples in H:H) tends to weaken the work.
That's all I can think of at the moment. I do hope it helps.
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Date: 2004-05-26 12:45 pm (UTC)Here's a hint: you can't.
A-bloody-men. I've only done two crossovers, one serious (SW/LotR, called "Not All Who Wander are lost") and one for laughs at
Wrong. Specifically because you're already asking people to accept "x" change, you have to be careful to keep everything else scrupulously faithful, to keep it plausible within the world.
And it's an important point that some things simply don't cross over well. Some do--I think Buffy and HP, despite the reams of horrible crossovers--make sense to mix because they have enough elements in common to have it be "seamless" without much effort, and where things are different, they can often be explained very easily (Oz's lycanthropy has a different pattern from Lupin's because of variant strains of the disease in Europe and North America; Willow's talent was always there as much as Hermione's, but the American system isn't as efficient in identifying Muggle-borns, etc). There was even a fairly believeable HP/Law and Order crossover on
Also, yes. Plot is a good thing. Have one.
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Date: 2004-05-26 12:45 pm (UTC)Dude(tte), that is so
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Date: 2004-05-26 12:55 pm (UTC)This is the first time somebody has ever done something like this for me. Thank you, Camwyn. I'm now going to let my overactive mind play with a Nightside/HP. I would suggest Simon R. Green to anybody. ((Nightingales Lament was great, Agents of Light and Darkness was exelent, and Something From the Nightside rocked me.))
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Date: 2004-05-26 12:57 pm (UTC)no subject
Date: 2004-05-26 12:58 pm (UTC)no subject
Date: 2004-05-26 01:00 pm (UTC)Yeah. I mean, geez, even if you cleared everything else away, you'd still be stuck with the fact that Ani's crimes very clearly belong in Federal court...
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Date: 2004-05-26 01:14 pm (UTC)He can find anything, but with a catch: It only works in the Nightside, the sick and secret neon noir, where gods and monsters walk side by side. That, and the catch is this, he uses it too often, and his enemys send their dogs. His enemys arn't nice people. Oh, that and theres the nagging suspiction that he caused the end of the world by going off to find his mother. (It involved a Timeslip) He also has a problem with friends. They all keep dying on him.
I can just SEE this happening:
The one with the pockeckmarked face raised an eyebrow, and laughed. "Oh? And how are you going to stop us?"
The three behind me looked like they were about to ask that, too. "Your wands don't have cores." I said, cooly.
They all looked at each other. A woman steped forward, and said "We'll see about that!" As she raised her wand, I raised my hands.
And let a steady stream of feathers, hairs, and what looked like heartstring fell to the floor. "Now go, before I decide to get nasty with your insides."
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Date: 2004-05-26 03:12 pm (UTC)no subject
Date: 2004-05-26 03:23 pm (UTC)no subject
Date: 2004-05-26 03:40 pm (UTC)You mentioned Darkover. I love you.
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Date: 2004-05-26 03:48 pm (UTC)I have to ask - are you a Da Vinci's Notebook fan? That looks like a possible quote from Internet Porn (possibly minus a girl or two, I forget). If you don't know them and it's not, you certainly should!
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Date: 2004-05-26 03:55 pm (UTC)no subject
Date: 2004-05-26 03:58 pm (UTC)They're a blast...
Date: 2004-05-26 04:45 pm (UTC)no subject
Date: 2004-05-26 06:42 pm (UTC)I'll second your echoing of this point here. (Now if someone repeats my seconding of your echoing of... Never mind.)
It doesn't even apply only to crossovers. A good rule of thumb of writing that I've seen is that you can get your audience to suspend their disbelief for something unusual -- once. Having a crossover, or an alternate history, or a stunning new development can work -- but most of the time, barring exceptional skill from the write, that has to be the only thing you're asking your reader to swallow, and it has to be well-supported and thoroughly thought-through by the writer. Explore its repercussions, come up with interesting secondary effects it might have, show sides of it your readers never would have imagined -- but stick to your premise. Otherwise... well, it can work, but it's asking for trouble. 'What if Harry had chosen Slytherin?' is a workable premise. 'What if the Ghostbusters visited Hogwarts?' is another, as
I've seen a story destroyed by just such a thing, actually. It started out as a fairly interesting alternate universe -- what if a certain incident in Sailor Moon's backstory had gone differently, and Usagi had ended up a scarred, streetwise orphan? It had its flaws, and the lead was a bit of a Mary Sue, but it was interesting nonetheless. Then, in a later chapter, with no foreshadowing, the supernatural villains from another series -- Blue Seed, I think, though I've never seen it -- appeared out of nowhere, and the alternate Usagi had her body taken over by a primordial force of vengeance or something like that. Threw the story into a screeching halt, and I don't think it recovered.
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Date: 2004-05-27 01:37 am (UTC)Must... not...
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Date: 2004-05-27 05:06 am (UTC)no subject
Date: 2004-05-27 07:09 pm (UTC)If not, er, consider yourself handed aforesaid big box.