Guys, I kind of need to know now, before I do any more work: Am I allowed to make the game Milliways in general, or would it be copyrighted (because of the book)? I do not want to fall into any copyright traps or anything.
Like: write and publish it.
Maybe into a Comp, depending if that's allowed.
Well, I'm not a practicing lawyer, and while I did study law and work on public policy none of that has anything to do with IP law. So I'm at best a slightly better informed layman (and only really know US law, not UK, though my understanding is that UK isn't that different). But my basic sense is that 1) from what you've described, yeah, it would violate Adams' copyright, but 2) no worse than any other piece of fan fiction violates the copyrights of the works on which they're based, and 3) since other pieces of fan fiction have been entered in to the Comp without any issues, I suspect you're fine
On IFDB, definitely.
Also, NB that the monetary damage you'd do to the Adams estate is basically zero -- like, there's no actual Milliways game for people to decide not to buy in favor of your thing -- so the absolute worst case scenario is probably just a cease and desist letter telling you to stop distributing the thing, not like thousands of dollars or anything
And that is only likely if you're making money on it.
(That would probably mean taking it down from IFDB, unfortunately -- but it seems very very unlikely to happen)
If the game isn't for sale anywhere, this is very unlikely.
...Which I wouldn't be...
Then you're likely fine.
Worse case scenario is a, "hey, don't do that" letter.
Well, they could ask you to take it down because one element of IP law is you need to demonstrate you've been defending it, even in the absence of damages. But I agree with pinkunz, I'd be comfortable running what seems like a very small risk with a very low downside
In the incredibly unlikely scenario of that happening, you'd just, not do that anymore as they asked.
(Since Adams was a UK citizen -- I think? Not sure if he ever got US citizenship -- and US/UK copyright law tends to be more protective than mot of the rest of the world, it's probably those that would be relevant here)
(Infocom probably didn't have any independent rights here -- they'd just have gotten a license from Adams for HHGH and Milliways, but those have probably long since expired. And as folks have noted in the main forum, Activision/Blizzard, who currently hold Infocom's IP, have been pretty laissez-faire about stuff)
TL;DR - In my case it’s Milliways, the Restaurant at the End of the Universe, but depending on the author and book, if you are writing an IF piece, as long as it is not monetized and on IFDB only (I’d assume) you would be a little better off. It would still be better to check.
Honestly, there are whole archives full of fanfiction for nearly every media property under the sun, and yeah, no one knows what would happen if non-monetized fanfiction was challenged in court, but the fact that it’s never been challenged, despite online fanfiction having been easily accessible for over 30 years, says to me that this isn’t a high priority for IP holders.
I mean, who knows, maybe you’d be the first, but if no one’s gone after Fanfiction.net or Wattpad or Archive of Our Own by now, the chances seem extremely slim. I also don’t see how it would matter whether it was hosted on the IF Archive only (I assume that’s what you mean, since IFDB doesn’t host games, just links to them) or elsewhere, as long as you aren’t charging money for it.
Re: “it’s always better to check,” if a fangame is being entered in a comp I agree it’s probably best to check with the organizer first, because some comps have rules about this sort of thing (and it’s not always clear where the line is), but if you’re releasing outside of a comp… well, you can run it by the forums if you like, but as long as you’re not charging money I think you’re always going to get the same answer.
Edit: To be clear, I’m not a lawyer and this isn’t legal advice, I’ve just been writing fanfiction for many years and I’ve seen the concerns about this wane as more and more time goes by without incident. That could of course always change! But even then I think they’d go after the abovementioned large fanfiction sites before they’d go after the IF Archive or individual authors.