Twin siblings, Sophie and Josh, lived pretty normal lives with archeologist parents and an aunt that lived in San Francisco where they were staying the summer when their lives turned upside down. While working in a book store, Josh meets the infamous Nicholas Flamel while he is attacked. After that, the twins end up on the run from monsters, gods, and immortals. And that was pretty much describing a premise of the first book. This entire series is a fast-paced rollercoaster of shadowrealms, ley gates, aura magic, and countless monsters and characters from history.
These books are definitely a conglomeration of knowledge that any young adult would have fun learning about.