From season 6, Stargate SG-1: Unnatural Selection concludes the tale spun in the prior episode, Prometheus. Oddly, the two stories aren’t really connected other than Prometheus being a way to get SG-1 into outer space so they can meet up with the Asgard and get involved in this second story.
I actually don’t mind this show as much I object to others. I find myself getting a bit intrigued by Sam’s relationship with Fifth. All of this happens, of course, after Thor enlists their help to repair a time dilation device which was meant to keep the Replicators at bay. This is way the team stays in outer space for a time, to save the day.
The stunning news is that the Replicators have found a way to take human form, one of them being the aforementioned Fifth, who is actually considered to be the weakest of the five human Replicators.
General Hospital’s Ian Buchanan played First with Patrick Currie as Fifth. Both did very well, and Currie was especially good. He actually recurred later on.
As I’ve often said, watch season 6 at your own risk. It’s just not the same as the other, better seasons, even though this one is decent.