Magic is Real
Idea
Magic is real, but only a small minority of humans regularly use magic. This minority is called the Unbound, and they include extraordinary leaders, soldiers, athletes, inventors, artists, entrepreneurs, and others. Many of the Unbound aren't even aware of their ability to directly tap belief, and instead explain their exceptionality as natural gifts, hard work, or luck. However, some Unbound discover or are taught the truth.
Some non-human beings and magical beings also secretly live on Earth, including some sentient beings. Throughout history, extraterrestrial and extradimensional beings and factions have contacted, visited, or migrated to Earth, influencing politics, science, culture, and ecosystems (including human evolution). Likewise, some humans have contacted, visited, or migrated to other planets and dimensions. Hence, many folktales, myths, and deities have at least threads of truth. All these secrets--the Unbound, magic, traffic with other worlds--is collectively called the Edge.
There are varied, conflicting explanations for the low prevalence and public awareness of magical and alien phenomena--that is, awareness of the Edge. Certainly, part of the charade is deliberate. Many contemporary factions compete to acquire and exploit magical technologies, alliances, and other resources. These factions include some nations and corporations, as well as some religious organizations, cults, secret societies, and the like. These factions usually act discreetly, both to hide their advantages and to avoid public confusion or panic (e.g., some fundamentalist religions would view most magic as evil). Many factions label their mutual agreement to keep magic a secret "the Lockbox Doctrine" (or simply "Lockbox").