Unknown to the majority of mankind, magic, spirits and other things you could call supernatural really exist. They have existed since the dawn of time, controlling many aspects of the world. When humans first appeared, it was unanimously decided by the supernatural world that it would be best for everybody if humanity never found out about them. Keeping the secret completely was impossible, which led to the birth of many pagan religions, witchcraft, mediums and similar things. Most of these cases were just people deluding themselves, but a select few were allowed to learn the truth and use the power that came with it.
Fast forward to early twenty first century. Most people firmly believe the supernatural is nothing more than myth, and the majority of those who think otherwise aren't anywhere close to the truth. A special organization (let's call them Wardens for now) exists which diligently regulates all interactions between human society and the supernatural side of the world. This organization is also a secret to the common man, its members leading seemingly ordinary lives among the unsuspecting masses. There are no incidents and all is well.
Then, completely unexpected, an unknown group attempts to capture one of the four seasons (they're spirits). Nothing is known about them: where they learned about the spirits, how they could have equipment capable of capturing one, what their goals are etc. However, it is the duty of the Wardens to stop them.
What I still need to figure out are the names for both organizations and a few other minor things.
Does this sound interesting?
