Saru returns to help the U.S.S. Discovery uncover the mystery of an unusually destructive new force. As Burnham leads the crew, she must also find a way to help Book cope with an unimaginable loss.

Sonequa Martin-Green (Captain Michael Burnham)
Doug Jones (Captain Saru)
Anthony Rapp (Lt. Cmdr. Paul Stamets)
Mary Wiseman (Lieutenant Sylvia Tilly)
Wilson Cruz (Dr. Hugh Culber)
Blu del Barrio (Ensign Adira Tal)
David Ajala (Cleveland Booker)

Oded Fehr (Admiral Charles Vance)
Ian Alexander (Gray Tal)
Chelah Horsdal (President Laira Rillak)
Tara Rosling (President T'Rina)
Annabelle Wallis (Zora)

Emily Coutts (Lt. Cmdr. Keyla Detmer)
Patrick Kwok-Choon (Lt. Cmdr. Gen Rhys)
Oyin Oladejo (Lt. Cmdr. Joann Owosekun)
Ronnie Rowe Jr. (Lt. Cmdr. Ronald A. Bryce)
Sara Mitich (Lt. Cmdr. Nilsson)
Luca Doulgeris (Leto)
Linford Mark Robinson (Starfleet Captain #1)
Katherine Trowell (Starfleet Captain #2)
Fabio Tassone (Book's Ship Computer)

• There is also an unrelated Star Trek Enterprise episode named "Anomaly" — episode 3 from Season 2.
  
• A Soong-type synth body is being built to house Gray's consciousness. They reference the low success rate of the transfer after it was first performed on Admiral Jean-Luc Picard (see the Star Trek: Picard episode "Et in Arcadia Ego, Part 2").
  
• Saru returns to Discovery and requests to be assigned as Burnham's first officer.