Oil change this evening. Dropped oil, nothing unusual except the plug was tight all the way out. Didn't think much of it, but went to refit and it wouldn't tighten. I was so very damn careful, as always, to make sure it was going in straight. Pulled it back out again and this lot came with it:
(that's the old copper washer - I was using a new one going back in)
That makes me very sad indeed

cleaning and poking at it confirms now have a very smooth sump plug hole. What is this second washer looking thing that's come out with it? It's a very soft metal. Is it proof of some previous repair? (hoping to be able to blame last guy

)
I'm reading a lot about helicoiling it to fix this, but I've not done this before. It doesn't seem too complicated, is this the on-your-back upside-down driveway repair that I'm looking at performing?
It really is true that nothing is as simple as it first seems with these vehicles.