IC post is up! Feel free to go ahead with your introductory posts. Let me know if anything's unclear or if you need more to go on! :D

Congratulations!
Your application for employment at TIN DRAGON DETECTIVE AGENCY has been accepted.
Before you can be officially hired as an official agent, officially, you must pass an introductory investigation assignment.
Please find enclosed an identification card that must be carried with you at all times. This card will grant you access to most restricted files and areas, and will act as proof of authority in most situations where such a thing might be useful in your work on behalf of the Agency. Losing or misusing this card will result in automatic failure of your introductory investigation.
Please find also enclosed a sum amount that will cover your travel expenses to the village of Riffraff. You will investigate the disappearance of two individuals: Kenver Edwards, 57, last seen four days ago; and Sewena Toll, 22, last seen yesterday morning.
Take the nearest drop-gate to Timber Moren. A lumber-wagon will be waiting for you and your fellow trainees to deliver you to Riffraff. The lumber-wagon departs at noon today. If you are not on it, you automatically fail your introductory investigation.
The driver has been instructed not to speak unless spoken to.
Good luck.
Each large town is built around its own drop-gate. The drop-gates are ancient circles of astranechite (a diamond-hard mineral, violet-black marbleized with pale green, one of only three minerals known to perpetually generate energy) embedded upright in the ground. A wide stone platform has been built around each drop-gate, and two gatekeepers posted as its sentry.
Each origin gatekeeper keeps a set of keys, one for each known drop-gate. Keys are circular, about the size of the palm of a hand, and usually made of metal or stone. The surface of the key is usually embellished with the insignia of the corresponding town or city. The underside of the key is a raised delicate pattern of lines and circles, entirely unique to each drop-gate.
The gatekeeper will usually charge a fee (sometimes very high) for passage through the gate. Upon acceptance of the fee, the gatekeeper will insert the corresponding key into a circular cavity on the side of the drop-gate. The marbleized stone will hum and vibrate slightly, but there is no other indication of activation. For exactly ten seconds after the key has been inserted, anyone or anything that passes through the drop-gate will step out on the other side of the gate at the chosen destination. Those unaccustomed to gate travel will, upon stepping through, experience a sense of vertigo and falling, which may last up to a few hours after travel.
The destination gatekeeper greets incoming travelers, gives directions, and calls for a wheelchair if the "dropped" traveler is unable to stand.