(Season Four episode list
here)
This is my ship! You can't take...uh, could you do that again?Enterprise encounters an Orion vessel, whose captain Harrad-Sar has an offer the Earthlings can't refuse. Archer and Reed go on board to hear the proposal: Harrad-Sar will give the coordinates to a planet rich in magnacite for Earth to exploit, and in return he will get a cut of the mining and processing operations. During the meeting he calls out three slave girls to dance for the guests (their worse-than-amateurish choreography offset by beauty and hyperactive pheromones - more on that in a bit), and the Orion captain offers them as a gift.
Archer takes them on board, intending to release them from their slavery when he finishes his current mission. The women prove to be a major distraction. The women - except for T'Pol - are suffering headaches; the men - except for Tucker (who is staying aboard to oversee repairs) and Phlox - are unusually antagonistic and delusional. Phlox himself is fighting an early triggering of his hibernation cycle. The doctor finds the culprit: potent pheromones inherent in Orion females. (I don't even wanna know what Augment medical technology would do to those pheromones...) Vulcans are evidently immune to the effect, and T'Pol theorizes that a quasi-psychic bond that had developed between herself and Tucker is passing on that immunity to him somehow.
The ship reaches the magnacite planet, and is fired upon by a craft less advanced than
Enterprise. Archer orders its destruction, Reed disobeys, and the ship moves off before Archer can fire on it himself. Kelby,
Enterprise's new chief engineer, sabotages the warp engines after a liaison with one of the Orion women. Archer discovers that the women had been in contact with Harrad-Sar, and has them held in decontamination.
The Orion ship arrives. The deal regarding the magnacite planet was a ruse to get the women on
Enterprise so they could use their hormonal powers of persuasion to arrange for crippling it. The Orion has a price on Archer's head for his previous encounter with them in the Augments three-parter, and Harrad-Sar intends to collect. He also reveals that he is under the womens' spell as much as most of Enterprise's crew. In Orion society, the women are the real rulers - which makes sense, considering their innate powers of suggestion.
Harrad-Sar attaches a grappling cable to the defenseless ship, but T'Pol and Tucker have a plan, just as the women arrive at the bridge after having escaped from decon. After stunning several of their crewmates with phase pistols, the two send an energy pulse through the cable and disable the Orion ship. The alien women are sent back to the Orion ship as the crew's pheromone high gradually tapers off. T'Pol admits to Tucker that she wants him back on board, and Tucker says he'd already put in for a transfer three days ago with Captain Hernandez to return to
Enterprise.
In the two-part episode set in the mirror universe, an Orion woman is seen among the crew of a Terran Empire ship. One suspects that the Empire woudl require her kind to take regular pheromone-suppressing medication - but it wouldn't surprise me if the Empire went to the extreme of having their pheromone-producing glands completely removed.