Lt. Worf must choose between his loyalty to Starfleet and his Klingon heritage when two Klingon fugitives take over the U.S.S. Enterprise.

The fugitives, yearning to recapture the Klingon fighting days of the past, hijack a Talarian vessel and destroy a Klingon ship sent to capture them. Then, just as their disabled ship is about to blow up, the Klingons are rescued by the U.S.S. Enterprise.

Unaware of the Klingons' true intentions, Captain Picard instructs Lt. Worf to show his Klingon comrades around the ship. During their tour, the fugitives attempt to enlist Worf in their cause. Meanwhile, a Klingon vessel approaches, and its captain informs Picard of the fugitives' crimes and demands their extradition. Before Picard can deliver them, one criminal escapes and the other is killed. The surviving Klingon takes over the engineering room and threatens to destroy the U.S.S. Enterprise.

Trying desperately to save the ship and its crew, Worf approaches the Klingon. Faced with certain death, the fugitive pleads with Worf once again to join him in his plan to escape with the battle section of the ship. Torn between his new life and his Klingon warrior instincts, Worf explains that the sign of the true warrior is not without — but within. The Klingon lunges but Worf, prepared for the move, kills the fugitive with a phaser blast.

Impressed by Worf's skills, the Klingon captain offers Worf a position under his command. After politely telling the Klingon captain he'll think about it, Worf assures Picard that he plans to remain with the U.S.S. Enterprise.