Years ago, Lt. Uhura befriended a diplomat from Eeiauo, the land of graceful, cat-like beings. The two women exchanged songs and promised never to reveal their secret—but now, those songs may be the only hope to save the planets from a deadly epidemic.

The U.S.S. Enterprise™ is orbiting Eeiauo in a desperate race to save the inhabitants before a deadly plague destroys them. Uhura's secret songs may hold the key to a cure—but the clues are veiled in layers of mystery and the inhabitants of Eeiauo aren't what they seem. But the plague is killing humans, threatening other planets—and Kirk must crack the code before the Starship Enterprise succumbs!