After stopping a vessel in space, Kirk and the crew find a very odd captain with a very strange cargo. The captain of the vessel is Harcourt Fenton Mudd – known as Harry to his friends – and the cargo are three lovely women he is transporting as brides for lonely men on distant planets. Kirk has a major problem: while trying to rescue Mudd and his women from his disintegrating ship, the Enterprise’s lithium crystals used to power the engines were destroyed. They travel to a nearby mining colony where Mudd sets about to arrange marriages for the women, interfering with Kirk’s plan to buy the crystals. All the time, the ship’s orbit is deteriorating and risks burning up in the atmosphere.