Spock and Burnham head to Talos IV, where the process of healing Spock forces the siblings to confront their troubled past. Stamets desperately tries to reconnect with an increasingly disconnected Hugh, while Tyler struggles to shed the crew’s suspicions of him due to his past as Voq.

Sonequa Martin-Green (Commander Michael Burnham)
Doug Jones (Commander Saru)
Anthony Rapp (Lt. Cmdr. Paul Stamets)
Mary Wiseman (Ensign Sylvia Tilly)
Shazad Latif (Agent Ash Tyler)
Wilson Cruz (Dr. Hugh Culber)
Anson Mount (Captain Christopher Pike)

Michelle Yeoh (Philippa Georgiou)
Melissa George (Vina)
Ethan Peck (Lt. Spock)
Alan van Sprang (Captain Leland)
Rachael Ancheril (Commander Nhan)
Dee Pelletier (Talosian)
Rob Brownstein (The Keeper)
Alisen Down (Starfleet Psychiatrist)
Hannah Cheesman (Lt. Cmdr. Airiam)
Emily Coutts (Lt. Keyla Detmer)
Patrick Kwok-Choon (Lt. Gen Rhys)
Oyin Oladejo (Lt. Joann Owosekun)
Ronnie Rowe Jr. (Lt. Ronald Bryce)
Julianne Grossman (Discovery Computer)
Arista Arhin (Young Michael Burnham)
Riley Gilchrist (Admiral Shukar)
Liam Hughes (Young Spock)
Harry Judge (Tellarite Admiral)
Jon De Leon (Section 31 Engineer)
Sara Mitich (Lt. Nilsson)
Tara Nicodemo (Admiral Patar)

• This episode opens with archival footage from the Original Series unaired pilot episode "The Cage", featuring Jeffery Hunter as Pike and Leonard Nimoy as Spock. The events of "The Cage" occurred three years before this episode.
  
• The computer warns Burnham that travel within the Talos star system is prohibited by Starfleet. Owosekun tell Pike the same thing when he orders the Discovery to jump there.
  
• Spock mind melded with the Red Angel, and it showed him the destruction of various Federation worlds, including Vulcan and Earth.
  
• Saru discovers someone has been transmitting extremely large bursts of data to an unidentified recipient.
  
• The reason for the distance between Michael and Spock is revealed. In an effort to push Spock away, she calls him a "weird little half-breed."
  
• This episode won an Emmy Award for Outstanding Prosthetic Makeup for a Series, Limited Series, Movie or Special.