Come Not Between the Dragons

News that the USS Lexington has been lost leaves Starfleet with only eight starships, and the crew are still absorbing the blow when an object travelling near light speed punches through the Enterprise hull. The intruder, a small stone-like being that sensors cannot detect, makes its way to the quarters of Ensign Eliza Taylor, who realises it is alive and afraid. Soon waves of energy sweep the ship, filling the crew with anger and suspicion. Even Spock is consumed by rage, and the stowaway, known as Usdi, becomes the focus of everyone's hostility, with Spock arguing that it should simply be handed over. Taylor and Counsellor McKennah take alpha wave inducers from sickbay and, with help from Uhura and Dickerson, hide Usdi in engineering. The devices break the spell, and the team traces the aggression to its source: a far larger being of the same kind, Usdi's father, who has been hunting him. Usdi places himself between his father and the ship, ending the conflict, and the two leave together. Later the Enterprise finds them in a comet cloud, where Taylor, drawing on painful memories of her own father, speaks to them about anger and fear and the hope that a parent and child can still reach each other.