It's nice to see Taggert again, and Matt Frewer seems to have toned down his performance (and accent) just a notch so he doesn't clash as much as he did in previous episodes. There are two ideas at work here. One is that the town works on a kind of biological principle in terms of climate control, plumbing and other essential functions - and is now out of wack. The other is that Carter has somehow heightened his pheromones, making him unnaturally attractive to women. While this leads to some interesting scenes, particularly when Jo can't resist Carter, overall this plot never really reaches critical mass. The same can be said about the town's "biology" going crazy. Neither story ever really kicks into gear. And while the editing and music tries to convince me it's an exciting climax, filtering out the spores just doesn't really have the impact that was intended.
There's some progress here in the story of Kevin and the Artifact. The big development centers on Stark's efforts to keep Henry away from the Artifact in order to protect Kevin. This of course frustrates Henry's efforts to find out how Beverly was involved with Kim's death. There's a moment between Henry and Stark that leaves open the distinct possibility that a confrontation between the two men is coming.
Carter has a nice moment with Callie, and Jo moves along with Zane. However, even these moments seem to fall a bit short for relationships this late in the season. Zoe isn't in this episode. Beverly hasn't been on the show for most of the season, and at this point all of the setup for the Artifact and "The Consortium" seems to have been abandoned. It's likely that these plot elements will show up again in the finale, but it's a letdown that these elements have been left out for so many episodes.
This isn't a bad episode of television, and has some funny and charming moments (as every episode of Eureka does), but it's one of the show's weaker efforts.