Arthur c Clark (the writer of 2001 a space odyssey) died in 2008, and the last book series he wrote on his deathbed was an "orthoquel" (look it up) series about the time traveling aliens that built the monoliths in 2001. (They’re basically archons).

https://youtu.be/DFLOuz6pXoI
https://youtu.be/gMq-I0dejjE
https://en.wikipedia.org/wiki/A_Time_Odyssey