Worf is concerned that his son Alexander pursue his Klingon heritage.
Alexander, Worf's son, has reached the age at which he should declare his desire to become a Klingon warrior. However, Worf is appalled to learn Alexander has no such intention.
While awaiting a rendezvous with the USS Kearsarge near the Vodrey Nebula, after listening to Worf's complaints about Alexander's rebellion and general attitude, Captain Picard suggests Worf should expose Alexander to more of his heritage, and the Enterprise stops at Maranga IV so the father and son can go to a Klingon festival.
The exposure to Klingon culture goes well for a time. However, while there, the two are confronted by three Klingon thugs. Before the assailants can mount an attack, a Klingon named K'mtar arrives and fights them off. K'mtar reveals that he is a distant relative who has come to protect Alexander.
K'mtar comes with Worf and Alexander back to the ship, and they quickly bond. Learning of Alexander's quandary, K'mtar assures the boy of the value of becoming a warrior. K'mtar agrees to help with Alexander's training, but after his initial attempts at teaching bear little fruit, K'mtar advises Worf to send Alexander away for training at a Klingon military academy. When Worf is reluctant to pursue this course, K'mtar threatens to use Klingon law and take custody of Alexander away from Worf.
Worf and K'mtar bicker until Alexander reminds them tartly that he is part-human on his mother's side. But both Worf and K'mtar conveniently forget this and insist that Alexander live fully the Klingon life. They just cannot agree, however, on who should finish raising Alexander. Worf is furious when K'mtar implies that Worf is a bad father and hotly fires back implications that K'mtar is a meddling busybody.
Meanwhile, the Enterprise crew is attempting to find out who attacked Worf and Alexander on Maranga IV. One dagger left behind had a mark from the House of Duras, and following this lead Riker and the crew locate the Duras sisters and accuse them of trying to assassinate Worf, which they deny vehemently. When the dagger is presented as evidence, the sisters make a disturbing discovery - several markings on the knife denote family members, including one for Lursa's son, even though Lursa herself only recently learned she was pregnant.
Meanwhile, Worf discovers K'mtar in Alexander's room, preparing to kill the boy. Alarmed and angry, Worf attacks K'mtar; once he is immobilized, K'mtar confesses that he was behind the attack, which he used to gain the trust of Worf and Alexander. Furthermore, he reveals that he is in fact Alexander - from the future - and he has come back in time to try to prevent Worf's murder.
The future Alexander had blamed himself for having allowed Worf to die, since he had never chosen the life of a Klingon warrior. Worf immediately realizes that K'mtar is in fact his adult son, and Worf tells him that he can only die happy if he knows he allowed Alexander to chart his own course. K'mtar leaves, to return to the future. Worf determines to approach his young son with a new attitude in the future.