A crewman has been murdered aboard the U.S.S. Trident, and all evidence points to Ensign Janos of the Excalibur. Captain Mackenzie Calhoun is reluctant to accept that Janos, a powerful non-humanoid whom the captain has known and trusted for years, could be a killer, and immediately launches an investigation into the crime. But this troubling murder mystery soon escalates into a full-fledged diplomatic crisis that threatens to pit Calhoun and Captain Elizabeth Shelby against the entire United Federation of Planets -- and the Starship Enterprise™.