The Great Calamity

William and Sammy are two regular teenagers who enjoy spending time together. There favorite activity is to explore abandoned buildings. One day as they are exploring an abandoned house, they come across lots of blood and multiple dead bodies. They decide to leave the house and call 911, but suddenly they hear a noise, so they go to check it out. They find one of the bodies gone. At that point they've decided that they have had enough and start to leave, but as they are close to the exit, sammy gets attacked. She kill the attacker and then they found out that the attacker was already dead, then they hear another crashing sound, and they find all the bodies gone, then they knew that this was only the beginning.