So in the Stargate, SG1 episode "Watergate" (no relation) it is revealed that the Soviets have their own DHD, which they grabbed off the Germans in 1945.
It is a bit of a weakness of the series that the US sat on their stargate until Catherine finally got them to restart it. Especially after the episode "Tantalus" revealed that Ernest Littlefield's group had successfully opened it in 1945. (And this without the ten years and four supercomputers Samantha Carter claimed had been necessary in 1998).
So...instead of a Manhattan Project, a crash project to open the Stargate. Because the Germans got theirs opened first (maybe they got the entire Giza gate -- and never you mind that outside of Indiana Jones movies they don't get to do what they like in Cairo in the 30's). Which means the US might have had to somehow discover the Antarctica gate...
But anyhow. The fun is having that same polyglot group of crazies, Feynman and Fermi and so forth, only working on wormhole physics. And Werner von Braun's group getting to explore the universe like they wanted, but without rockets. Of course the physics of the gate means that Tantalus and Abydos are the most likely successful contacts anyhow. Which ends up with one side joining forces with Ra and then things really get crazy.
But let's shake it up a little. Instead of the usual suspects for heroes and villains, have the US play Ra like an analog of Stalin, handling him with what they think is a long enough spoon at least until the Germans are out of the picture. Except they don't know about the Goa'uld parasite. And it is left up to a third party to try to save more than one world from the madness.
Some really motivated Italians, perhaps? Why is it that the role of being the only heroes who can fight well enough always goes to the ones who, historically, had the kick-ass armies in the first place? But, alas, that's too much research. As is the obvious Bear in the room (Soviet Russia, that is.) Or even further afield, China (who had enough on their plates already, and besides, let's keep this to the Western Front). Ah, but given the fun of pitting the Manhattan Project against von Braun's rocket group, who else but to throw in the mix are those doughty and reliable underdog heroes, Bletchly Park and Alan Turing and so forth...I speak of course of the Brits.
The other bunny of the day is even odder. So when the reboot Tomb Raider 2013 was made Crystal Dynamics re-used some assets. The rusty, tramp-steamer-looking Endurance which Whitman's archaeological expedition charters re-uses the model of the two big fancy cargo ships Amanda has in the final game of the previous canon (aka Tomb Raider: Underworld).
But...what if it is the same ship? Ten years, rough seas and a few more changes of ownership (plus Lara did a number on one of the ships anyhow. Sunk it, actually, but who's counting).
And once again let's skip the stupid island so conveniently filled with soft targets and spare clips for the various machine guns lying around like a cheap first-person shooter. Instead, assume the previous canon is true. At least as far as Amanda and Natla (though, pretty obviously, Natla didn't actually destroy the world in this chronology). Lara might or might not be real; it would be interesting to have her as a reclusive countess with stories about her past that sound downright mythic.
But she's not our protagonist. Our protagonist is stumbling across, on that same ship, evidence of a story that already happened.
Which is not to say it isn't a story that's been concluded! Lara might not be holed up in Abbingdon and not talking to anyone, but Natla is still out there and dangerous as ever. One might reach at this point for "Young" Lara, the inexperienced college student of the reboot. But that ship has already been around the world a few times. Instead, try someone else for the starring role. But keep the other characters.
I think this is actually more interesting. Stephanie, say, might be discovering there's a darker side to archaeology. And she has to reach out to people who have the skills she needs now, but people who don't have that existing relationship to her. Like Conrad Roth, who in this chronology is friends only with Angus Grim and isn't already staged as a mentor and trainer and dead father figure to the protagonist de jour.
(Actually, in a way it is even more hilarious to make Roth the hero. He'd very much fit the archetype of a certain kind of masculine adventure fiction; he's practically an early Alister MacClean protagonist. So he'd be retired, going to seed, his only contact with military adventure being the stories he shares with his mate Grim. Content to captain this ship around even if the current charter are a bunch of idiots. Until they discover more than they can handle and he has to step up to the plate.)
(And there's everything such a character could want. A young man -- or young woman -- to take on as protege, at least a couple options for romance, an abrasive academic who thinks he should be in charge, a gentle giant and a tough cop as solid right hands and a geek for tech support.)
These are wild plot bunnies, of course. I'm not petting them. I'm pretty much done with those two silly universes anyhow (at least, I will be in another four to six chapters).