Back aboard the Enterprise, Uhura is alarmed by the behavior of the men in the crew, all of whom appear to have been intoxicated by exposure to the signal from the planet. Forced by these circumstances to relieve a lackadaisical Chief Engineer Scott and take command herself, Lieutenant Uhura makes Nurse Christine Chapel the starship's temporary chief medical officer. On the planet, the members of the landing party take doses of the stimulant cortropine from Dr. McCoy's medical kit in an effort to slow down the aging process. Spock, the least weakened of the team because of his Vulcan physiology, manages to get his hands on one of the communicators that their female captors had confiscated. Before the women render him unconscious and recapture him, Spock manages to contact the Enterprise long enough to make it clear to Uhura that the landing party is in dire need of rescue. Because no women have fallen victim to the strange signal from the Taurean world, Uhura organizes an armed, all-female team and leads it in an assault against the women on the planet's surface. Faced with Uhura's threat of destroying their temple with the Enterprise's phaser banks, the landing party's captors surrender, explaining that their race had fled to this world from their own dying planet, only to learn too late that the Taurean planet drains away the vital energies of humanoid life forms.

As the Taurean women are unable to leave the planet, they must recharge their depleted energies once every 27.346 years by luring passing starships to them and draining the men aboard of their life forces. At Spock's suggestion, the rescued landing party members use the molecular memory of the Enterprise's transporter to restore them to their normal ages, and Kirk agrees to use his starship to relocate the Taurean women to a more suitable planet.