Without warning, they detect another vessel closing on them, of an Orion designation. On the Huron's bridge, Captain O'Shea's freighter gets underway with the drug shipment. When Spock protests, McCoy asserts, ' Doctor's orders.' When Spock leaves Kirk says, ' It'll hurt seeing him like that.' McCoy agrees adding, ' As much as it may seem at times that I can't stand that pointy-eared encyclopedia, I don't want to see that happen to him.' In a briefing room, Kirk informs Spock of the situation and tells him his duty time has been cut in half. The starship Potemkin has already picked up the drug and will transfer it to a freighter, the SS Huron for delivery to the Enterprise. We have arranged to get the strobolin needed to save Mr. Then, by the end of the third day it will be irreversible. McCoy can slow it down with injections from a synthesized drug, but Spock only has two days before the disease builds up immunity to the drug. The drug is found on only a few worlds in the galaxy, the closest of which, Beta Canopus, is four days away at maximum warp speed. A synthesized drug can control the disease, but only naturally-occurring strobolin will cure it. The infection enters the bloodstream and encases the cells so they cannot carry oxygen, resulting in suffocation. Spock has contracted the disease, which, because of their copper-based blood, is fatal to Vulcans. While underway, however, Spock loses consciousness on the bridge and is taken to sickbay. McCoy says the disease is no longer even as serious as pneumonia and there should be no problem completing our present mission, representing the Federation at the dedication ceremonies for the new Academy of Science on Deneb V.' The outbreak of choriocytosis aboard the Enterprise seems to be under control.

Summary ' Captain's log, stardate 6334.1.

Star trek orion pirates