Tuesday's dinner was effectively ruined, the meat for the dinner proved to be contaminated with some sort of plastic! It reminded me of the sort of plastic you find under the glass lids of higher-end brands of instant coffee, or perhaps the seals used in food producing machinery (it didn't take much imagination to figure it was probably part of the sausage machine).
I won't name the retailer, as I don't think it warrants hysteria, but I certainly didn't feel like going in and making a scene... so what to do? Off to their website, where I found contact information. They wanted all sorts of things like the best-before date, batch number and so on - but we bought it in a 24-pack and then split them up into 6 individual groups, and the recyling had already been so getting the packaging back was out of the question. I filled the form out as best I could anyway, and sent it off along with an attached picture of what we'd scavanged.
"Debbie" called us early the next day - her team leader was out of the office for the day but she wanted to clarify a few things (is anyone sick, was there any dental damage, etc). After a brief conversation she arranged to call back, and did so today. They don't need us to keep the samples and leftovers, we can discard them, and they'll send us a letter with an apology, explanation, and a refund.
I suppose that's good enough for me, I don't even really know what I was expecting to happen but this seems a satisfactory outcome.