The Chosen, Part 2: Blood Enemies

The Chosen, Part 2 of 3. The Enterprise rushes to answer a distress call from Starbase 7, finding only wreckage where the base should be. The attack echoes a recent assault on a Klingon outpost, and all evidence points to the Romulans. Kirk is ordered to work alongside a civilian specialist to learn the truth...but the answers may prove lethal.