Great photo!
As for the non-likeability of Thinnes as David Vincent, here's what classic TV expert Stephen Bowie wrote about what the producers and viewers thought at the time:
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Though they acknowledged the script problems, Martin and Alan Armer also suspected that there was an even more...
I feel the same way about The Invaders as I do about the sport of soccer. I admire it from a technical perspective. But I don't find it particularly enjoyable to watch. It's well-produced, well-directed and well-acted, with a lot of night-for-night shooting and obvious high-quality production...