Icepezz will probably do a better job, but to make a very long story very short, all in town was (mostly) calm until a metting at a tavern became a little strained when a magic user blatantly used his healing power, earning a sword pointed at his face. Just when things started to settle down a burning skeleton came about and bumped into the shop. When that skeleton was "killed", all literal hell broke loose when a popular and presently quite active bar went up in flames and every single former occupant came out in the form of burning skeletons spreading fire and their own state upon others. The guards attempt to battle the skeletons with a few heros that had come in; meanwhile, others are trying to take down the demon who is at the root of the issue.

In the background, a demon plans to assassinate the leader of the town. 

That's putting it in a very simplified form.