While exploring a group of devastated class-M planets in a remote sector of space, the crew of the U.S.S. Enterprise is shocked to discover a group of human slaves on a forbidding, glacial world. The slaves' revolt against their human overseers, and Captain Picard and his crew sympathize with the slaves plight but cannot interfere in the conflict.
After the revolt succeeds, Captain Picard learns that both the slaves and the overseers were controlled by a mysterious bird-like race called the Tseetsk, who are coming to reclaim their property. With time running out, the rebels kidnap Captain Picard and Counselor Troi, drawing the U.S.S. Enterprise into the middle of their deadly plan of vengeance.