After the Queen of Egypt has been murdered, her American-raised daughter assumes the throne, but she soon learns has the power to decide who lives or dies in this sci-fi thriller set in 3010. [secret Underworld: define what you mean better - like the actual underworld?] Not sure if this logline is what your story actually is, but focus on what are the two difficult/impossible choices the daughter has: she must decide whether to wield the power of the Underworld or go back to college exams, or she must learn to become queen of country and the afterlife or face (stakes). Hope that helps!

Thank you, Noel Thompson! This was immensely helpful!