This reminds me of my own funny catastrophe. Moved into this house in August. The following January we had a couple visit us, with their newly adopted baby. It was very, very cold. So, for the first time in my new house, I lit a fire. I grew up with fireplaces, and my dad put a fireplace insert in our house in Manchester that we ran all winter to help reduce heating costs. It was a lifesaver in the ice storm of 1973. So I didn't consider myself a novice.
Every fireplace I'd used had a manual flu, where you reach inside and set the damper open, part open or closed. Simple. This one has a brass knob. So I turned it a few times, assuming that must get it to full open, and started a fire. Unfortunately, I did a good job building the fire and in moments it was roaring and the room filled with smoke. Then the whole downstairs filled with smoke. We opened every window and door on a nice zero degree day as I tried to put out the fire. Eventually had to dump water on it, which mixed with ash and ran down to the carpet from our raised hearth. It took weeks to get rid of the smoke smell and hours for it to clear. Hardwood floors went in that room not long after.
Later I learned that to open the flu I have to turn that knob like 50 times (how stupid is that) as it very slowly cranks open. This was 20 years ago and my wife still gives me dirty looks if I even suggest having a fire. I definitely eye test the flu if I do.