Ravaged by a killer virus, the Romulans enter Canara, where the only antidote can be found. Desperate, they incite a victorious U.S.S. Enterprise attack on one of their vessels, but Kirk discovers their ruse.

Meanwhile the central computer has fallen in love with him, severely crippling the Starship Enterprise. Somehow Kirk must overcome the lovesick computer and bring the antidote to the Romulans, before the galaxy crashes over the brink of war.