After my guests had departed, I went to the property and upon opening the door smelled a very strong odor of smoke. I then saw the visible smoke damage all over the white painted brick fireplace, ceiling, walls and ceiling molding. The guest had permission to use the fireplace and a Duraflame Log was placed in the fireplace for them. I have guests arriving in 2 days and don't even know if I will be able to be able to get the home smelling normal again in time for there arrival. The guests did not tell me anything about a fireplace malfunction or problem so, I can only assume that they did not open the flue initially. The fireplace was tested some time ago and worked properly. There is a chimney cap on the chimney so that not animals can make home inside the chimney. Has anyone had this unfortunate problem. So upsetting not to even have been told by the guests. How would you handle this?