As the DMA approaches Earth and Ni’Var, Captain Burnham and the crew of the U.S.S. Discovery attempt to make first contact with the powerful species responsible before it’s too late.

Sonequa Martin-Green (Captain Michael Burnham)
Doug Jones (Captain Saru)
Anthony Rapp (Lt. Cmdr. Paul Stamets)
Wilson Cruz (Dr. Hugh Culber)
Blu del Barrio (Ensign Adira Tal)
Tig Notaro (Commander Jett Reno)
David Ajala (Cleveland Booker)

Shawn Doyle (Dr. Ruon Tarka)
Chelah Horsdal (President Laira Rillak)
Tara Rosling (President T'Rina)
Annabelle Wallis (Zora)
Hiro Kanagawa (Dr. Hirai)
Phumzile Sitole (General Ndoye)

Emily Coutts (Lt. Cmdr. Keyla Detmer)
Patrick Kwok-Choon (Lt. Cmdr. Gen Rhys)
Oyin Oladejo (Lt. Cmdr. Joann Owosekun)
Sara Mitich (Lt. Cmdr. Nilsson)
Orville Cummings (Lieutenant Christopher)
David Benjamin Tomlinson (Lieutenant Linus)
Jahkeil Goldson (Science Officer)
Fabio Tassone (Book's Ship Computer)

• Mary Wiseman (Sylvia Tilly) does not appear in this episode and her name does not appear in the opening credits.
  
• This episode debuted simultaneously with the Picard episode "Penance".