I'm trying to identify an episode of a 60's or 70's sci-fi TV series where a group of military people (and possibly scientists) in a very secluded base in possibly arctic or Antarctica are visited by a group of people and possibly a dog(?).
Each of these visitors are known by the people at the base but they were all known to be deceased. There was a wife, parents, etc. The visitors explain that there has been a discovery of some kind to bring people back to life, which they find hard to believe of course, but the people are there so even though skeptical they allow them into the base. They slowly start to realize that something's not quite right...
I can't remember much more detail or the ending - maybe aliens that took the appearance & personality based on the thoughts of the base guys?
I've searched for this show several times over the years with no luck. For some reason the show stuck with me and I'd love to see it again, even though I might be disappointed.