There’s a backward planet whose society is built around debt bondage- almost everyone is a slave or indentured servant to one degree or another (even slaves sometimes have sub-slaves) except for a tiny class of “contract holders” at the top. The planet has some contact with the rest of the galaxy via a spaceport where interstellar traders bring in goods.
The story revolves around a woman who is a Navigator: one of a handful of people having a rare savant talent for guiding starships through hyperspace. While on shore leave on that planet she comes to the attention of a decadent contract holder who becomes determined to enslave her for himself by tricking her into violating a local law. Navigators are so precious that ordinarily any Navigator who runs afoul of a planet’s local laws is ransomed out, but the contract holder doesn’t want a ransom, he wants her. If he insists on going through with it the Navigators will embargo the planet, which the other Contract Holders fear would cause a revolution. So aside from the Navigator’s personal peril there’s the political intrigue around her case.