Harry Potter and the Philosopher's/Sorcerer's Stone

The beginning of the story about Harry Potter, and the mysterious object hidden at the school, sought after by the evil wizard that tried to kill Harry as a baby in his hopes of achieving immortality for himself. Though the attempt to kill baby Harry failed, and "He-Who-Must-Not-Be-Named" was bodily destroyed, his spirit endured, and after a decade, Voldemort has returned to the wizarding world to try to achieve immortality with the assistance of the real-world mythological ingredient to create the Elixor of Life, which can also turn lead into gold. But, of course, not all is as it seems.

Though this book serves to introduce the characters and the plot of a fun story, it also introduces real history and mythology, stuff that all of us muggles can look up in our local public library, and likely many of us have some of the Stone's history on our shelves already: The Bible. The Stone dates back to King Solomon, just before David (the kid that killed Goliath) was anointed King of Israel. Though The Bible doesn't delve into the Stone, there are other writings dating back to Solomon which very much do describe the Stone, and a lot of other magick (notice the addition of the k). The Keys of Solomon is a collection of scrolls describing the Stone and other alchemical and magickal objects and "prayers," or spells... And this is the beauty of J.K.'s writing, the level of research she put into creating her world and the histories within it. So much is real-world, muggle knowledge. And everything has a purpose within the story, from the names of characters, spells, locations, to each little event that corresponds to something later in the same book or in a later book.