Star Trek VI The Undiscovered Country. Praxis, the Klingon moon explodes and brings chaos to the Empire. Since they have 70 years of oxygen left, the Federation wants to help them and they will dismantle many bases along the Federation-Klingon Neutral Zone. Kirk is selected to escort Chancellor Gorkon to Earth for a series of diplomatic conversations and a cloaked B'rel class Bird-of-Prey attacks Gorkon's ship (Qo'noS One, a K'tinga class heavy cruiser). Kirk and McCoy are accused of assassinating the Chancellor and are sent to the penal asteroid of Rura Penthe. Spock mounts a rescue and Kirk prepares a jailbreak and escapes. The Enterprise warps to Khitomer to avoid the assassination of the President of the United Federation of Planets and avoid an interstellar war between the two superpowers. They fight against General Chang and arrest the corrupt Federation officers, the Romulan ambassador and save the Alpha Quadrant.