Unlike David McCallum's intellectual (and married) Daniel Westin, Sam Casey was a bell-bottom bluejeans/denim-shirt wearing, hunky "everyman" in the Steve Austin mold, and not tied down by the bounds of matrimony. But that wasn't enough to bring in viewers, and Gemini Man folded quicker than its predecessor, cancelled after airing only five episodes.
Eleven episodes were shot in all, and were shown in syndication (and later on the Sci-Fi Channel), and a couple were edited together into "movies" for TV and home video release (one of these was skewered by the 'bots of MST3K in one of it's later seasons).
I was not a fan of this show... and I haven't seen an episode since the Spring of '76. One of these days, I guess I'll need to revisit it.