How Do You Hide the Magic in Urban Fantasy?
No real magic
No one believes in magic anymore
In the wake of the success of Twilight, most urban fantasy these days tends toward teen paranormal romance but there is more to the genre. In some ways urban fantasy goes back to fantasy's roots, in stories that assumed the audience would believe the supernatural to be real. When Dickens wrote A Christmas Carol he didn't need to cast the tale in a fantasy world to get the audience to believe a man might be visited by spirits. Modern urban fantasy though has an audience that is less likely to believe in magic or monsters and certainly assumes the rest of the world doesn't. Consequently urban fantasy assumes that the supernatural is somehow hidden from the majority of the world.
Comedy is hard
Dying is easy,
In some cases like “The Munsters,” or “Bewitched,” storytellers go to the absurd length of having the general population simply refuse to believe in anything abnormal, even if they see it with their own eyes. Occasionally this is given some justification because those who do believe are shown to have their sanity doubted and may end up being institutionalized. More often though the supernatural occurs right behind peoples backs and the effects are shrugged off. Most often this is done specifically as comedy so the audience isn't supposed to consider how a world full of these oddities would be ignored.
Alice about to step through
All we have is a door
A common serious treatment of fantasy overlapping the real world is to present the only magic in our world being a means to access an alternate reality. Examples of this are found in the Narnia, Witchworld and Landover series among others. Though most of these stories barely fit under the label urban fantasy, with most of the narrative and it's fantastic elements being set in the other world. Sometimes though transit back and forth between the two worlds is an important element of the plot. In the Landover series, for example, a subconscious belief in magic in our world was necessary to the survival of the other.
What if we just can't see them?
Invisible to the mundane world
Another means of presenting fantasy elements side by side with the real world is to posit that members of the mundane population simply lack the ability to see some fantastic creatures. In the Harry Potter series for example muggles cannot see dementors or similar creatures. A similar explanation was used by White Wolf Games “World of Darkness” setting several years before to hide the existence of creatures like werewolves. While such an explanations works for rare or harmless creatures, if dangerous invisible magical monsters that threaten human life are presented as common it strains the credulity of the audience.
The most common means of hiding the fantastic elements of an urban fantasy setting from the world is conspiracy. Whether it be the “Ministry of Magic” from Harry Potter or the “Volturi” from Twilight some organization keeps the normal population from learning the truth. Generally if such an organization is not international in reach it has the cooperation of similar groups worldwide. Some conspiracies have rather benign methods to hide the existence of the supernatural (memory altering magic for example). Others are quite brutal eliminating any who threaten to expose the secret. Unfortunately for the believably of these tales any conspiracy relies on the ability of everyone who knows the secret keeping it.
Hiding is easy if you leave no witnesses
Finally there are stories, often horror, that don't hide the supernatural at all. They simply rely on fantastic items and creatures being so rare that they only affect those who encounter them personally. Many of these tales are stand alone stories that focus on the effects of the brief events when an individual or small group encounter these rare or unique things as in The Mummy. In horrific tales this encounter usually leaves few (perhaps one) survivors who are seldom believed. Sometimes sequels are spawned about the next group to encounter the creature or object but the longer the story goes on the harder it becomes to believe the truth will remain hidden. Non horror stories of this sort generally rely on a creature like the titular Water Horse that is sufficiently sympathetic that those who encounter it are willing to keep it secret and safe from those that might exploit it.
We all wish we were the one to find the truth
Regardless of how (or if) the supernatural is hidden in urban fantasy, stories in this genre almost always begin with the truth being revealed. Sometimes this reveal is the result of careful investigation by the viewpoint character after they have noticed one or more oddities in the world around them. Just as often though the reveal is entirely accidental. In either case, unless the story is horror, the protagonist often has some special quality that makes them useful enough to those who keep the secret that they are trusted with it. The main character is also special in some way in stories where the hidden world of the fantastic is deliberately revealed. Regardless of how the truth is revealed, the main character is often destined to some great role in the hidden world of fantasy. It is perhaps this last element as much as the wish to see some magic in the world around us that gives urban fantasy it's popularity. We all hope that we might find ourselves to be the one destined for greatness. If that greatness brings with it a world far more interesting than the mundane one we live in, so much the better.