I know what you mean gramywheels. I watched the last few of season 2 elsewhere and also the first three episodes of season 3 too. You are right you do need to watch season 2 before this one as there are new characters and things happened to old characters too, in fact it was excellent viewing. Episode one season 3 is a double episode but that is one and two together, and then I watched three. I am up to The last stone but can't find it anywhere. I don't understand the listings on this site they don't make sense and I don't want to click on one to check the episode and waste points as I don't think they are correct. I can give you the site I watched the beg of season 3 on if you want? Also season 2. Let me know.
Nik x0)