Face to face with Kliingon vessels, the U.S.S. Shenzhou prepares for the possibility of war if negoations fail. Amidst the turmoil, Burnham looks back to her Vulcan upbringing for guidance.

Sonequa Martin-Green (Cmdr. Michael Burnham)
Doug Jones (Lt. Commander Saru)
Shazad Latif (Lt. Ash Tyler)
Anthony Rapp (Lt. Paul Stamets)
Mary Wiseman (Cadet Sylvia Tilly)
Jason Isaacs (Captain Gabriel Lorca)

Michelle Yeoh (Captain Philippa Georgiou)

Mary Chieffo (L'Rell)
James Frain (Ambassador Sarek)
Kenneth Mitchell (Kol)
Chris Obi (T'Kuvma)
Terry Serpico (Admiral Brett Anderson)
Sam Vartholomeos (Ensign Danby Connor)

Arista Arhin (Young Michael Burnham)
Emily Coutts (Lt. Keyla Detmer)
Javid Iqbal (Voq)
Ali Momen (Lt. Kamran Gant)
Clare McConnell (Dennas)
Thamela Mpumlwana (Young T'Kuvma)
Damon Runyan (Ujilli)
Tasia Velnza (Computer Voice)
Chris Violette (Lt. Britch Weeton)
Romaine Waite (Lt. Troy Januzzi)

• T'Kuvma wants to unite the warring 24 Klingon Great Houses. He does this by provoking the Federation and starting a war. When he lights the beacon, the great houses each send a ship. Not all of the houses join T'Kuvma, but the ones that do engage the Federation fleet in battle.
  
• During the battle, the U.S.S. Shenzhou is lost, and the U.S.S. Europa and the other Starfleet ships are destroyed.
  
• After disabling the Klingon ship of the dead, Georgiou and Burnham beam over to capture T'Kuvma. Captain Georgiou is killed by T'Kuvma in this episode, and Burnham in turns kills T'Kuvma.
  
• At the end of the episode, Cmdr. Burnham is court-martialed, stripped of rank, and sentenced to life imprisonment.
  
• Though credited in the title sequence, Shazad Latif (Tyler), Anthony Rapp (Stamets), Mary Wiseman (Tilly), and Jason Isaacs (Lorca) do not actually appear in this episode. The U.S.S. Discovery also does not appear in this episode.