During an investigation of a radiation anomaly, the Enterprise is met by a Klingon warship bearing Ambassador K'Ehleyr. When she beams aboard to meet with Captain Picard, she brings a surprise for Lt. Worf — her young son, who is also Worf's son. While Worf is faced with conflicting feelings for K'Ehleyr and his child, Picard must confront a momentous task. Klingon High Council Leader K'Mpec has been poisoned and is on his deathbed. Knowing he doesn't have long to live, he summons Picard to arbitrate the imminent power struggle for leadership of the Klingons. One of the two contenders is also K'Mpec's murderer, and the fragile peace between the Federation and the Klingons depends on Picard's ability to discover who is the traitor — before he becomes the new Klingon leader.

Suzie Plakson (Ambassador K'Ehleyr)
Robert O'Reilly (Gowron)
Patrick Massett (Duras)
Charles Cooper (Chancellor K'Mpec)
Jon Steuer (Alexander)
April Grace (Transporter Chief Hubbell)
Michael Rider (Security Guard)
Basil Wallace (Klingon Guard #1)
Mirron E. Willis (Klingon Guard #2)

• Duras kills K'Ehleyr when she learns why Worf was discommendated. The producers decided to kill the popular K'Ehleyr because they felt it was the best way to provoke Worf into killing Duras.
  
• K'Ehleyr and Worf mated in the 2nd season episode "The Emissary". Alexander is awfully big for a one-year-old.... Alexander goes to live with Worf's foster parents, and he returns to the Enterprise to stay in the fifth season episode "New Ground".
  
• The new Klingon Vor'cha-class attack cruiser debuts here. (All other Klingon vessels where rehashed from the classic Trek movies up to this point.) The ship now has warp nacelles, which have a slight "Starfleet" look to reflect the Klingon-Federation alliance.
  
• K'Mpec has been Chancellor of the Klingon Empire longer than any other.
  
• The Klingon storyline continues in the season finale "Redemption, Part I", where Gowron is officially installed as Chancellor of the Klingon Empire.