Star Trek The Next Generation S3 E18 Allegiance

Captain Picard is kidnapped and replaced by a doppelgänger, while imprisoned with diverse captives, he uncovers a test of leadership. The crew doubts the impostor's actions, leading to a confrontation with alien species testing leadership qualities. Picard's ingenuity leads to escape, revealing the impostor as an alien projection, emphasizing the themes of leadership and trust.