The starship Enterprise arrives at Star Base 11 after having sustained severe damage from an ion storm, which has also resulted in the death of one crewmember, Lt. Comdr. Ben Finney. An examination of the ship's computer log shows that, contrary to his own account, Captain James T. Kirk (William Shatner) apparently violated regulations by prematurely jetisoning the ion pod in which Finney was stationed. Rumors start to spread that, despite the supposed friendship between the two men, Finney nursed a grudge against Kirk -- which the captain knew about -- derived from an incident during their service together years earlier and the fact that Kirk had moved past the older officer to become a starship commander. Based on the computer record, the star base commander, Commodore Stone (Percy Rodriguez), believes Kirk to be guilty of either negligence or something worse, and urges him to resign for the good of the service. Kirk, however, insists on a full court martial that will either clear him or destroy his career.