A temporal distortion brings back an old love of Picard.
The Enterprise receives a distress call from a scientist, Dr. Paul Manheim, who is working on time experiments at a remote research station. His work is causing odd distortions, repeating moments and strange rifts in time that threaten the region. His wife Jenice turns out to be a woman from Picard's past.
The episode is a bittersweet look at the Captain's romantic history, and a reminder of an old regret from his days in Paris. It uses a time-distortion plot to create tension, but is mostly about people rather than technology. The title is a nod to the famous film Casablanca. It is a gentle, character-driven episode in the middle of the first season.