Since I got quite a few hits on my Monster Roster, I thought I'd include the introduction too. It's a little cheesy, but keep in mind I'm doing this campaign for my little brothers and sisters:
d20 Halloween Campaign
You all enter a metallic room from different doors, there's a circular table in the middle of the room with what looks like a large computer monitor built into the center. Other TV and computer monitors line the walls above the doors, all of them off.
A week ago you received a letter in the mail asking you to meet at this address at this appointed time. The letter had a plane ticket to Atlanta Georgia, and one thousand dollars enclosed. It said simply that more money would come your way if you agreed to come along. You can only assume that the others coming into the room got the same letter.
You can introduce yourselves.
The only door that hasn't been opened starts to creak. A sliver of dim light fall through the opening of the door. An average height man with average features and brown hair steps into the room, closing the door behind him. He nods to each of you, and sits at the table.
"Since you've probably all introduced each other, I'll skip right to why you are here. I represent Department Thirteen, and we take care of things that shouldn't happen. There is a situation in Eastern Europe that needs to be attended to. One of the small villages that our base buys vegetables from has become a ghost town. We first lost contact with them a month ago. When we sent agents to the town, we lost contact with them also. We received only this, a small satellite video. The image is so dark that it's virtually worthless, but the audio is what made us send for all of you."
The man pushes and invisible button near the screen in the middle of the table. The monitor comes alive with a static image. The volume must be on its maximum setting. All you can hear is "What are those things?!" and a mixture of scuffling, rusting, and gunfire. After a minute, only rustling can be heard, then only silence. The man pushes another button and the screen disappears.
"We want to fly you in to this small farming village in the mountains to find out what is going on. We've selected each of you for your skills and talents. We can't tell you what to expect, but we can promise a large payoff. Each of you should have already received a fraction of your payment in advance."
The man stands up and says, "You leave immediately. Follow me." He stands, walks to the door he came out of, and opens it wide. The room is flooded with light.
When your eyes adjust, you see a private jet on a landing strip.
What do you want to do?
The flight goes quickly, you land in a dark forest in a fortified military base. The walls are easily 40 ft high with razor wire along the top. You are rushed from the jet to a large helicopter. No sooner are you in the walls of the base, than the helicopter takes you right back out... deeper into the forested mountains.
The chopper touches down outside a small farming village. A wooden gate seems to close in the small cottages and fields. The sun has just set, and the only light comes from a waxing moon. The pilot says that she'll be back at sunrise to pick you up at this same place.