Stargate: Through Time and Space
In 1995 an academic called Danielle Jackson was trying to persuade her peers that the Egyptian gods, and many others from mythology were aliens. Laughed out of the debate, she left chagrined, angry and desperate. It was not until she was approached and asked to join Norad in translating some rather old Egyptian which she believed could be far older than first thought. With her help they managed to translate key symbols and principles behind the object. When Colonel O'Neil allowed the actual gate to be unveiled she knew that something monumental was about to occur. Twenty hours later they went through the gate to arrive on a planet the locals called Abydos.
After exploring for a few hours Danielle disappeared deep within the local pyramid on an expedition, searching for the key to allow them to return home. It was not until she sat and thought about her findings over the evening meal that the concepts began to solidify within her brain. That the local stars within the pyramid seemed to resemble those found on Earth was interesting, but left many problems. It was not until the arrival of Ra that things became crystal clear.
Abydos was Earth, just a different universe, or timeline. It was just so much Star Trek to her and it needed the physicists back home to resolve the riddles therein. Shortly after being shot, and killed, and then resurrected within the sarcophagus that real fear set in. That perhaps the Gods of Earth existed back home, and would one day return. After the death of the Egyptian god, teams continued to go through the gate, and in each one they found instances of divergence from Earth. One planet had a current Roman Empire, another was run by Genghis Khan's distant relatives that had subjugated the whole world, again where Hitler is still alive and breathing thanks to occult and arcane sciences. In each and every one they encountered a race known as the Goa'uld.
In many cases the same one was encountered on multiple worlds, something that scared Sam Carter to virtually wetting himself. the fact was that the Goa'uld were multiversal conquerors, intent on taking over every Earth they came across. Yet it seemed that their technology and knowledge were at a massive disparity. Many seemed barely able to fix what SG Teams broke. So either they did not own the technology, or something more was at work here. Their servants the Jaffa were horrendously competent army that used advanced technology and tactics, set ambushes and traps - some even had cybernetic attachments. They seemed a positive smorgasbord of personnel. Not all of them were even human.
For any one familiar with Gurps Alternate Earth books, this is very much built upon that theme. For this RP you are not limited to being human. Would there be any interest in this?