Riker's secret about a past mission puts him at odds with Picard.
Admiral Erik Pressman arrives on the Enterprise with an urgent mission, and Riker, who once served under him, is happy to see him. The mission is a secret one, to recover the wreck of the Pegasus, a ship that Riker served on years earlier. Riker has to face a long-held secret about what happened on that ship.
The story concerns an experimental cloaking device and a mutiny, and the moral dilemma is a hard one for Riker. Picard has to decide between loyalty to Starfleet and the Federation's treaty with the Romulans. The episode is a tense drama about honor and obedience, and it is a standout of the final season.