In the world of The Dresden Files, magic—as well as vampires, demons, spirits, faeries, werewolves, outsiders, and other monsters—is real, and while the supernatural is still widely discredited, it is practiced by some members of society. Additionally, large portions of the globe (such as much of Central and South America) are mentioned as being largely under the control of supernatural factions. The White Council is an organization of human wizards, noted to wield significant economic power in the world, along with their supernatural power. Each species in the series (humans, faeries, vampires, etc.) has its own political and societal rules and organizations. The human wizards depend on the White Council, while faeries may belong to either of two Faerie Courts, or none at all. Vampires may belong to any of four vampire courts.
Harry Dresden works as the world's only "consulting wizard", accepting supernatural cases from both human and nonhuman clients, as well as the Chicago PD's Special Investigation unit. As the series progresses, Dresden takes on an increasingly important role in the supernatural world at large, as he works to protect the general public, making getting by as a working wizard and private investigator difficult for him. He finds himself facing off against an increasing variety of creatures (including other wizards), while facing the realization that his various cases may all be tied together behind the scenes and that his role might be even greater than he is willing to admit.
My friend Heather wanted to run this using a mash up of the FATE RPG rules and D6. So I created one version that was close to FATE, but then I ended up creating another one closer to what Heather wanted. Magic system went through 3 iterations. Two are here on the site.
Addendum 10/26/22: Well, Heather wants to run this again, but requested it be more like Star Wars D6. So instead of translating the FATE mechanics over, I started from scratch and translated the Dresdenverse over to D6. Much better. This is hopefully the last time I need to change the rules around. I feel like this is the definitive edition.