"Based on" is the significant phrase here.

Nefertari, Ramses II, Howard Carter, QV66, the elicit trade in antiquities, and even the Annunaki (who were mythical Mesopotamian gods) have some form of existence here in the actual real world. All of them can be found in Wikipedia, if you're interested to learn more.

With regard to the supposed curse that hit Howard Carter's team after they discovered King Tut's tomb, it's pretty much banana oil. There is no written curse anywhere in the tomb, all of the deaths associated with the tomb have natural causes and occurred over a long period of time, and Carter himself died of leukemia 17 years later. There's nothing to the curse except our own delight in scary stories -- and the media's fascination with selling more newspapers.